The fusion of a spermatozoon (SPERMATOZOA) with an OVUM thus resulting in the formation of a ZYGOTE.
An assisted reproductive technique that includes the direct handling and manipulation of oocytes and sperm to achieve fertilization in vitro.
Mature male germ cells derived from SPERMATIDS. As spermatids move toward the lumen of the SEMINIFEROUS TUBULES, they undergo extensive structural changes including the loss of cytoplasm, condensation of CHROMATIN into the SPERM HEAD, formation of the ACROSOME cap, the SPERM MIDPIECE and the SPERM TAIL that provides motility.
Interactive processes between the oocyte (OVUM) and the sperm (SPERMATOZOA) including sperm adhesion, ACROSOME REACTION, sperm penetration of the ZONA PELLUCIDA, and events leading to FERTILIZATION.
A mature haploid female germ cell extruded from the OVARY at OVULATION.
Female germ cells derived from OOGONIA and termed OOCYTES when they enter MEIOSIS. The primary oocytes begin meiosis but are arrested at the diplotene state until OVULATION at PUBERTY to give rise to haploid secondary oocytes or ova (OVUM).
The transfer of mammalian embryos from an in vivo or in vitro environment to a suitable host to improve pregnancy or gestational outcome in human or animal. In human fertility treatment programs, preimplantation embryos ranging from the 4-cell stage to the blastocyst stage are transferred to the uterine cavity between 3-5 days after FERTILIZATION IN VITRO.
The fertilized OVUM resulting from the fusion of a male and a female gamete.
A tough transparent membrane surrounding the OVUM. It is penetrated by the sperm during FERTILIZATION.
An assisted fertilization technique consisting of the microinjection of a single viable sperm into an extracted ovum. It is used principally to overcome low sperm count, low sperm motility, inability of sperm to penetrate the egg, or other conditions related to male infertility (INFERTILITY, MALE).
Movement characteristics of SPERMATOZOA in a fresh specimen. It is measured as the percentage of sperms that are moving, and as the percentage of sperms with productive flagellar motion such as rapid, linear, and forward progression.
The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.
Somewhat flattened, globular echinoderms, having thin, brittle shells of calcareous plates. They are useful models for studying FERTILIZATION and EMBRYO DEVELOPMENT.
The ratio of the number of conceptions (CONCEPTION) including LIVE BIRTH; STILLBIRTH; and fetal losses, to the mean number of females of reproductive age in a population during a set time period.
The cap-like structure covering the anterior portion of SPERM HEAD. Acrosome, derived from LYSOSOMES, is a membrane-bound organelle that contains the required hydrolytic and proteolytic enzymes necessary for sperm penetration of the egg in FERTILIZATION.
The earliest developmental stage of a fertilized ovum (ZYGOTE) during which there are several mitotic divisions within the ZONA PELLUCIDA. Each cleavage or segmentation yields two BLASTOMERES of about half size of the parent cell. This cleavage stage generally covers the period up to 16-cell MORULA.
Changes that occur to liberate the enzymes of the ACROSOME of a sperm (SPERMATOZOA). Acrosome reaction allows the sperm to penetrate the ZONA PELLUCIDA and enter the OVUM during FERTILIZATION.
Substances or mixtures that are added to the soil to supply nutrients or to make available nutrients already present in the soil, in order to increase plant growth and productivity.
The structural and functional changes by which SPERMATOZOA become capable of oocyte FERTILIZATION. It normally requires exposing the sperm to the female genital tract for a period of time to bring about increased SPERM MOTILITY and the ACROSOME REACTION before fertilization in the FALLOPIAN TUBES can take place.
Diminished or absent ability of a female to achieve conception.
Morphological and physiological development of EMBRYOS.
Preservation of cells, tissues, organs, or embryos by freezing. In histological preparations, cryopreservation or cryofixation is used to maintain the existing form, structure, and chemical composition of all the constituent elements of the specimens.
A post-MORULA preimplantation mammalian embryo that develops from a 32-cell stage into a fluid-filled hollow ball of over a hundred cells. A blastocyst has two distinctive tissues. The outer layer of trophoblasts gives rise to extra-embryonic tissues. The inner cell mass gives rise to the embryonic disc and eventual embryo proper.
Techniques for the artifical induction of ovulation, the rupture of the follicle and release of the ovum.
The inability of the male to effect FERTILIZATION of an OVUM after a specified period of unprotected intercourse. Male sterility is permanent infertility.
Inability to reproduce after a specified period of unprotected intercourse. Reproductive sterility is permanent infertility.
Proteins which are found in eggs (OVA) from any species.
The injection of very small amounts of fluid, often with the aid of a microscope and microsyringes.
Endometrial implantation of EMBRYO, MAMMALIAN at the BLASTOCYST stage.
The capacity to conceive or to induce conception. It may refer to either the male or female.
The plasma membrane of the egg.
Morphological and physiological development of EMBRYOS or FETUSES.
A unisexual reproduction without the fusion of a male and a female gamete (FERTILIZATION). In parthenogenesis, an individual is formed from an unfertilized OVUM that did not complete MEIOSIS. Parthenogenesis occurs in nature and can be artificially induced.
The anterior portion of the spermatozoon (SPERMATOZOA) that contains mainly the nucleus with highly compact CHROMATIN material.
Results of conception and ensuing pregnancy, including LIVE BIRTH; STILLBIRTH; SPONTANEOUS ABORTION; INDUCED ABORTION. The outcome may follow natural or artificial insemination or any of the various ASSISTED REPRODUCTIVE TECHNIQUES, such as EMBRYO TRANSFER or FERTILIZATION IN VITRO.
The process by which semen is kept viable outside of the organism from which it was derived (i.e., kept from decay by means of a chemical agent, cooling, or a fluid substitute that mimics the natural state within the organism).
Procedures to obtain viable OOCYTES from the host. Oocytes most often are collected by needle aspiration from OVARIAN FOLLICLES before OVULATION.
The process of germ cell development in the female from the primordial germ cells through OOGONIA to the mature haploid ova (OVUM).
Artificial introduction of SEMEN or SPERMATOZOA into the VAGINA to facilitate FERTILIZATION.
The fluid surrounding the OVUM and GRANULOSA CELLS in the Graafian follicle (OVARIAN FOLLICLE). The follicular fluid contains sex steroids, glycoprotein hormones, plasma proteins, mucopolysaccharides, and enzymes.
Methods pertaining to the generation of new individuals, including techniques used in selective BREEDING, cloning (CLONING, ORGANISM), and assisted reproduction (REPRODUCTIVE TECHNIQUES, ASSISTED).
A subphylum of chordates intermediate between the invertebrates and the true vertebrates. It includes the Ascidians.
Echinoderms having bodies of usually five radially disposed arms coalescing at the center.
The entity of a developing mammal (MAMMALS), generally from the cleavage of a ZYGOTE to the end of embryonic differentiation of basic structures. For the human embryo, this represents the first two months of intrauterine development preceding the stages of the FETUS.
A pair of highly specialized muscular canals extending from the UTERUS to its corresponding OVARY. They provide the means for OVUM collection, and the site for the final maturation of gametes and FERTILIZATION. The fallopian tube consists of an interstitium, an isthmus, an ampulla, an infundibulum, and fimbriae. Its wall consists of three histologic layers: serous, muscular, and an internal mucosal layer lined with both ciliated and secretory cells.
A type of CELL NUCLEUS division, occurring during maturation of the GERM CELLS. Two successive cell nucleus divisions following a single chromosome duplication (S PHASE) result in daughter cells with half the number of CHROMOSOMES as the parent cells.
The element in plants that contains the female GAMETOPHYTES.
An OOCYTE-containing structure in the cortex of the OVARY. The oocyte is enclosed by a layer of GRANULOSA CELLS providing a nourishing microenvironment (FOLLICULAR FLUID). The number and size of follicles vary depending on the age and reproductive state of the female. The growing follicles are divided into five stages: primary, secondary, tertiary, Graafian, and atretic. Follicular growth and steroidogenesis depend on the presence of GONADOTROPINS.
Extracts of urine from menopausal women that contain high concentrations of pituitary gonadotropins, FOLLICLE STIMULATING HORMONE and LUTEINIZING HORMONE. Menotropins are used to treat infertility. The FSH:LH ratio and degree of purity vary in different preparations.
The discharge of an OVUM from a rupturing follicle in the OVARY.
A gonadotropic glycoprotein hormone produced primarily by the PLACENTA. Similar to the pituitary LUTEINIZING HORMONE in structure and function, chorionic gonadotropin is involved in maintaining the CORPUS LUTEUM during pregnancy. CG consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is virtually identical to the alpha subunits of the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity (CHORIONIC GONADOTROPIN, BETA SUBUNIT, HUMAN).
The thick, yellowish-white, viscid fluid secretion of male reproductive organs discharged upon ejaculation. In addition to reproductive organ secretions, it contains SPERMATOZOA and their nutrient plasma.
Transfer of preovulatory oocytes from donor to a suitable host. Oocytes are collected, fertilized in vitro, and transferred to a host that can be human or animal.
The granulosa cells of the cumulus oophorus which surround the OVUM in the GRAAFIAN FOLLICLE. At OVULATION they are extruded with OVUM.
A trypsin-like enzyme of spermatozoa which is not inhibited by alpha 1 antitrypsin.
Clinical and laboratory techniques used to enhance fertility in humans and animals.
The technique of maintaining or growing mammalian EMBRYOS in vitro. This method offers an opportunity to observe EMBRYONIC DEVELOPMENT; METABOLISM; and susceptibility to TERATOGENS.
A count of SPERM in the ejaculum, expressed as number per milliliter.
Passive or active movement of SPERMATOZOA from the testicular SEMINIFEROUS TUBULES through the male reproductive tract as well as within the female reproductive tract.
The deposit of SEMEN or SPERMATOZOA into the VAGINA to facilitate FERTILIZATION.
A phylum of the most familiar marine invertebrates. Its class Stelleroidea contains two subclasses, the Asteroidea (the STARFISH or sea stars) and the Ophiuroidea (the brittle stars, also called basket stars and serpent stars). There are 1500 described species of STARFISH found throughout the world. The second class, Echinoidea, contains about 950 species of SEA URCHINS, heart urchins, and sand dollars. A third class, Holothuroidea, comprises about 900 echinoderms known as SEA CUCUMBERS. Echinoderms are used extensively in biological research. (From Barnes, Invertebrate Zoology, 5th ed, pp773-826)
Occurrence or induction of release of more ova than are normally released at the same time in a given species. The term applies to both animals and humans.
Methods used to induce premature oocytes, that are maintained in tissue culture, to progress through developmental stages including to a stage that is competent to undergo FERTILIZATION.
The reproductive organ (GONADS) in female animals. In vertebrates, the ovary contains two functional parts: the OVARIAN FOLLICLE for the production of female germ cells (OOGENESIS); and the endocrine cells (GRANULOSA CELLS; THECA CELLS; and LUTEAL CELLS) for the production of ESTROGENS and PROGESTERONE.
The event that a FETUS is born alive with heartbeats or RESPIRATION regardless of GESTATIONAL AGE. Such liveborn is called a newborn infant (INFANT, NEWBORN).
The total process by which organisms produce offspring. (Stedman, 25th ed)
A major gonadotropin secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Follicle-stimulating hormone stimulates GAMETOGENESIS and the supporting cells such as the ovarian GRANULOSA CELLS, the testicular SERTOLI CELLS, and LEYDIG CELLS. FSH consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity.
The convoluted cordlike structure attached to the posterior of the TESTIS. Epididymis consists of the head (caput), the body (corpus), and the tail (cauda). A network of ducts leaving the testis joins into a common epididymal tubule proper which provides the transport, storage, and maturation of SPERMATOZOA.
A condition of suboptimal concentration of SPERMATOZOA in the ejaculated SEMEN to ensure successful FERTILIZATION of an OVUM. In humans, oligospermia is defined as a sperm count below 20 million per milliliter semen.
A growth from a pollen grain down into the flower style which allows two sperm to pass, one to the ovum within the ovule, and the other to the central cell of the ovule to produce endosperm of SEEDS.
The performance of dissections, injections, surgery, etc., by the use of micromanipulators (attachments to a microscope) that manipulate tiny instruments.
The condition of carrying two or more FETUSES simultaneously.
Diseases involving the FALLOPIAN TUBES including neoplasms (FALLOPIAN TUBE NEOPLASMS); SALPINGITIS; tubo-ovarian abscess; and blockage.
The developmental entity of a fertilized egg (ZYGOTE) in animal species other than MAMMALS. For chickens, use CHICK EMBRYO.
The posterior filiform portion of the spermatozoon (SPERMATOZOA) that provides sperm motility.
Contraceptive methods based on immunological processes and techniques, such as the use of CONTRACEPTIVE VACCINES.
A complication of OVULATION INDUCTION in infertility treatment. It is graded by the severity of symptoms which include OVARY enlargement, multiple OVARIAN FOLLICLES; OVARIAN CYSTS; ASCITES; and generalized EDEMA. The full-blown syndrome may lead to RENAL FAILURE, respiratory distress, and even DEATH. Increased capillary permeability is caused by the vasoactive substances, such as VASCULAR ENDOTHELIAL GROWTH FACTORS, secreted by the overly-stimulated OVARIES.
Undifferentiated cells resulting from cleavage of a fertilized egg (ZYGOTE). Inside the intact ZONA PELLUCIDA, each cleavage yields two blastomeres of about half size of the parent cell. Up to the 8-cell stage, all of the blastomeres are totipotent. The 16-cell MORULA contains outer cells and inner cells.
The emission of SEMEN to the exterior, resulting from the contraction of muscles surrounding the male internal urogenital ducts.
The phase of cell nucleus division following PROMETAPHASE, in which the CHROMOSOMES line up across the equatorial plane of the SPINDLE APPARATUS prior to separation.
The reproductive cells of plants.
Male germ cells derived from the haploid secondary SPERMATOCYTES. Without further division, spermatids undergo structural changes and give rise to SPERMATOZOA.
The male gonad containing two functional parts: the SEMINIFEROUS TUBULES for the production and transport of male germ cells (SPERMATOGENESIS) and the interstitial compartment containing LEYDIG CELLS that produce ANDROGENS.
Compounds which increase the capacity to conceive in females.
Substances that provide protection against the harmful effects of freezing temperatures.
The part of a cell that contains the CYTOSOL and small structures excluding the CELL NUCLEUS; MITOCHONDRIA; and large VACUOLES. (Glick, Glossary of Biochemistry and Molecular Biology, 1990)
Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.
Proteins found in SEMEN. Major seminal plasma proteins are secretory proteins from the male sex accessory glands, such as the SEMINAL VESICLES and the PROSTATE. They include the seminal vesicle-specific antigen, an ejaculate clotting protein; and the PROSTATE-SPECIFIC ANTIGEN, a protease and an esterase.
The fertilizing element of plants that contains the male GAMETOPHYTES.
Elements of limited time intervals, contributing to particular results or situations.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
The maturing process of SPERMATOZOA after leaving the testicular SEMINIFEROUS TUBULES. Maturation in SPERM MOTILITY and FERTILITY takes place in the EPIDIDYMIS as the sperm migrate from caput epididymis to cauda epididymis.
A species of the true toads, Bufonidae, found in South America.
The encapsulated embryos of flowering plants. They are used as is or for animal feed because of the high content of concentrated nutrients like starches, proteins, and fats. Rapeseed, cottonseed, and sunflower seed are also produced for the oils (fats) they yield.
Expulsion of the product of FERTILIZATION before completing the term of GESTATION and without deliberate interference.
The quality of SEMEN, an indicator of male fertility, can be determined by semen volume, pH, sperm concentration (SPERM COUNT), total sperm number, sperm viability, sperm vigor (SPERM MOTILITY), normal sperm morphology, ACROSOME integrity, and the concentration of WHITE BLOOD CELLS.
Women who allow themselves to be impregnated with the understanding that the offspring are to be given over to the parents who have commissioned the surrogate.
An early embryo that is a compact mass of about 16 BLASTOMERES. It resembles a cluster of mulberries with two types of cells, outer cells and inner cells. Morula is the stage before BLASTULA in non-mammalian animals or a BLASTOCYST in mammals.
Hormones that stimulate gonadal functions such as GAMETOGENESIS and sex steroid hormone production in the OVARY and the TESTIS. Major gonadotropins are glycoproteins produced primarily by the adenohypophysis (GONADOTROPINS, PITUITARY) and the placenta (CHORIONIC GONADOTROPIN). In some species, pituitary PROLACTIN and PLACENTAL LACTOGEN exert some luteotropic activities.
Procedures to obtain viable sperm from the male reproductive tract, including the TESTES, the EPIDIDYMIS, or the VAS DEFERENS.
The removal of secretions, gas or fluid from hollow or tubular organs or cavities by means of a tube and a device that acts on negative pressure.
Sexual activities of animals.
Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).
The process of germ cell development in the male from the primordial germ cells, through SPERMATOGONIA; SPERMATOCYTES; SPERMATIDS; to the mature haploid SPERMATOZOA.
An exotic species of the family CYPRINIDAE, originally from Asia, that has been introduced in North America. They are used in embryological studies and to study the effects of certain chemicals on development.
A potent synthetic analog of GONADOTROPIN-RELEASING HORMONE with D-serine substitution at residue 6, glycine10 deletion, and other modifications.
Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.
An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.
The potential of the FETUS to survive outside the UTERUS after birth, natural or induced. Fetal viability depends largely on the FETAL ORGAN MATURITY, and environmental conditions.
The transformation of a liquid to a glassy solid i.e., without the formation of crystals during the cooling process.
Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)
Chemical agents that increase the permeability of biological or artificial lipid membranes to specific ions. Most ionophores are relatively small organic molecules that act as mobile carriers within membranes or coalesce to form ion permeable channels across membranes. Many are antibiotics, and many act as uncoupling agents by short-circuiting the proton gradient across mitochondrial membranes.
A decapeptide that stimulates the synthesis and secretion of both pituitary gonadotropins, LUTEINIZING HORMONE and FOLLICLE STIMULATING HORMONE. GnRH is produced by neurons in the septum PREOPTIC AREA of the HYPOTHALAMUS and released into the pituitary portal blood, leading to stimulation of GONADOTROPHS in the ANTERIOR PITUITARY GLAND.
The 17-beta-isomer of estradiol, an aromatized C18 steroid with hydroxyl group at 3-beta- and 17-beta-position. Estradiol-17-beta is the most potent form of mammalian estrogenic steroids.
A group of simple proteins that yield basic amino acids on hydrolysis and that occur combined with nucleic acid in the sperm of fish. Protamines contain very few kinds of amino acids. Protamine sulfate combines with heparin to form a stable inactive complex; it is used to neutralize the anticoagulant action of heparin in the treatment of heparin overdose. (From Merck Index, 11th ed; Martindale, The Extra Pharmacopoeia, 30th ed, p692)
Ducts that serve exclusively for the passage of eggs from the ovaries to the exterior of the body. In non-mammals, they are termed oviducts. In mammals, they are highly specialized and known as FALLOPIAN TUBES.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Signal transduction mechanisms whereby calcium mobilization (from outside the cell or from intracellular storage pools) to the cytoplasm is triggered by external stimuli. Calcium signals are often seen to propagate as waves, oscillations, spikes, sparks, or puffs. The calcium acts as an intracellular messenger by activating calcium-responsive proteins.
The major progestational steroid that is secreted primarily by the CORPUS LUTEUM and the PLACENTA. Progesterone acts on the UTERUS, the MAMMARY GLANDS and the BRAIN. It is required in EMBRYO IMPLANTATION; PREGNANCY maintenance, and the development of mammary tissue for MILK production. Progesterone, converted from PREGNENOLONE, also serves as an intermediate in the biosynthesis of GONADAL STEROID HORMONES and adrenal CORTICOSTEROIDS.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action during the developmental stages of an organism.
A technique that came into use in the mid-1980's for assisted conception in infertile women with normal fallopian tubes. The protocol consists of hormonal stimulation of the ovaries, followed by laparoscopic follicular aspiration of oocytes, and then the transfer of sperm and oocytes by catheterization into the fallopian tubes.
A genus of SEA URCHINS in the family Toxopneustidae possessing trigeminate ambulacral plating.
The process of germ cell development from the primordial GERM CELLS to the mature haploid GAMETES: ova in the female (OOGENESIS) or sperm in the male (SPERMATOGENESIS).
A potent synthetic agonist of GONADOTROPIN-RELEASING HORMONE with 3-(2-naphthyl)-D-alanine substitution at residue 6. Nafarelin has been used in the treatments of central PRECOCIOUS PUBERTY and ENDOMETRIOSIS.
The reproductive cells in multicellular organisms at various stages during GAMETOGENESIS.
An enzyme that catalyzes the random hydrolysis of 1,4-linkages between N-acetyl-beta-D-glucosamine and D-glucuronate residues in hyaluronate. (From Enzyme Nomenclature, 1992) There has been use as ANTINEOPLASTIC AGENTS to limit NEOPLASM METASTASIS.
Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations, or by parent x offspring matings carried out with certain restrictions. All animals within an inbred strain trace back to a common ancestor in the twentieth generation.
The age of the mother in PREGNANCY.
Determination of the nature of a pathological condition or disease in the OVUM; ZYGOTE; or BLASTOCYST prior to implantation. CYTOGENETIC ANALYSIS is performed to determine the presence or absence of genetic disease.
A phylum of metazoan invertebrates comprising the segmented worms, and including marine annelids (POLYCHAETA), freshwater annelids, earthworms (OLIGOCHAETA), and LEECHES. Only the leeches are of medical interest. (Dorland, 27th ed)
Gonadotropins secreted by the pituitary or the placenta in horses. This term generally refers to the gonadotropins found in the pregnant mare serum, a rich source of equine CHORIONIC GONADOTROPIN; LUTEINIZING HORMONE; and FOLLICLE STIMULATING HORMONE. Unlike that in humans, the equine LUTEINIZING HORMONE, BETA SUBUNIT is identical to the equine choronic gonadotropin, beta. Equine gonadotropins prepared from pregnant mare serum are used in reproductive studies.
Glycosidic antibiotic from Streptomyces griseus used as a fluorescent stain of DNA and as an antineoplastic agent.
Nutritive tissue of the seeds of flowering plants that surrounds the EMBRYOS. It is produced by a parallel process of fertilization in which a second male gamete from the pollen grain fuses with two female nuclei within the embryo sac. The endosperm varies in ploidy and contains reserves of starch, oils, and proteins, making it an important source of human nutrition.
A division of predominantly marine EUKARYOTA, commonly known as brown algae, having CHROMATOPHORES containing carotenoid PIGMENTS, BIOLOGICAL. ALGINATES and phlorotannins occur widely in all major orders. They are considered the most highly evolved algae because of their well-developed multicellular organization and structural complexity.
A light microscopic technique in which only a small spot is illuminated and observed at a time. An image is constructed through point-by-point scanning of the field in this manner. Light sources may be conventional or laser, and fluorescence or transmitted observations are possible.
The fundamental dispositions and traits of humans. (Merriam-Webster's Collegiate Dictionary, 10th ed)
The reproductive organs of plants.
A condition of having no sperm present in the ejaculate (SEMEN).
Methods of maintaining or growing biological materials in controlled laboratory conditions. These include the cultures of CELLS; TISSUES; organs; or embryo in vitro. Both animal and plant tissues may be cultured by a variety of methods. Cultures may derive from normal or abnormal tissues, and consist of a single cell type or mixed cell types.
The point at which religious ensoulment or PERSONHOOD is considered to begin.
A major gonadotropin secreted by the human adenohypophysis (PITUITARY GLAND, ANTERIOR). Follicle-stimulating hormone stimulates GAMETOGENESIS and the supporting cells such as the ovarian GRANULOSA CELLS, the testicular SERTOLI CELLS, and the LEYDIG CELLS. FSH consists of two noncovalently linked subunits, alpha and beta. The alpha subunit is common in the three human pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity.
The state that distinguishes organisms from inorganic matter, manifested by growth, metabolism, reproduction, and adaptation. It includes the course of existence, the sum of experiences, the mode of existing, or the fact of being. Over the centuries inquiries into the nature of life have crossed the boundaries from philosophy to biology, forensic medicine, anthropology, etc., in creative as well as scientific literature. (Random House Unabridged Dictionary, 2d ed; Dr. James H. Cassedy, NLM History of Medicine Division)
Two individuals derived from two FETUSES that were fertilized at or about the same time, developed in the UTERUS simultaneously, and born to the same mother. Twins are either monozygotic (TWINS, MONOZYGOTIC) or dizygotic (TWINS, DIZYGOTIC).
A technique in assisted reproduction (REPRODUCTIVE TECHNIQUES, ASSISTED) consisting of hormonal stimulation of the ovaries, follicular aspiration of preovulatory oocytes, in-vitro fertilization, and intrafallopian transfer of zygotes at the pronuclear stage (before cleavage).
Methods for controlling genetic SEX of offspring.
The transfer of POLLEN grains (male gametes) to the plant ovule (female gamete).
Glycoproteins found on the membrane or surface of cells.
A potentially life-threatening condition in which EMBRYO IMPLANTATION occurs outside the cavity of the UTERUS. Most ectopic pregnancies (>96%) occur in the FALLOPIAN TUBES, known as TUBAL PREGNANCY. They can be in other locations, such as UTERINE CERVIX; OVARY; and abdominal cavity (PREGNANCY, ABDOMINAL).
A potent synthetic long-acting agonist of GONADOTROPIN-RELEASING HORMONE that regulates the synthesis and release of pituitary gonadotropins, LUTEINIZING HORMONE and FOLLICLE STIMULATING HORMONE.
The period of the MENSTRUAL CYCLE representing follicular growth, increase in ovarian estrogen (ESTROGENS) production, and epithelial proliferation of the ENDOMETRIUM. Follicular phase begins with the onset of MENSTRUATION and ends with OVULATION.
Cellular proteins encoded by the c-mos genes (GENES, MOS). They function in the cell cycle to maintain MATURATION PROMOTING FACTOR in the active state and have protein-serine/threonine kinase activity. Oncogenic transformation can take place when c-mos proteins are expressed at the wrong time.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Sexual union of a male and a female in non-human species.
Embryonic and fetal development that takes place in an artificial environment in vitro.
Agglutination of spermatozoa by antibodies or autoantibodies.
Cellular release of material within membrane-limited vesicles by fusion of the vesicles with the CELL MEMBRANE.
Microscopy of specimens stained with fluorescent dye (usually fluorescein isothiocyanate) or of naturally fluorescent materials, which emit light when exposed to ultraviolet or blue light. Immunofluorescence microscopy utilizes antibodies that are labeled with fluorescent dye.
Human artificial insemination in which the husband's semen is used.
The number of births in a given population per year or other unit of time.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
Minute cells produced during development of an OOCYTE as it undergoes MEIOSIS. A polar body contains one of the nuclei derived from the first or second meiotic CELL DIVISION. Polar bodies have practically no CYTOPLASM. They are eventually discarded by the oocyte. (from King & Stansfield, A Dictionary of Genetics, 4th ed)
The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.
Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.
A class in the phylum MOLLUSCA comprised of SNAILS and slugs. The former have coiled external shells and the latter usually lack shells.
Liquids transforming into solids by the removal of heat.
Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.
Human artificial insemination in which the semen used is that of a man other than the woman's husband.
Warm-blooded vertebrate animals belonging to the class Mammalia, including all that possess hair and suckle their young.
The commonest and widest ranging species of the clawed "frog" (Xenopus) in Africa. This species is used extensively in research. There is now a significant population in California derived from escaped laboratory animals.
Deliberate breeding of two different individuals that results in offspring that carry part of the genetic material of each parent. The parent organisms must be genetically compatible and may be from different varieties or closely related species.
Methods of implanting a CELL NUCLEUS from a donor cell into an enucleated acceptor cell.
Intracellular messenger formed by the action of phospholipase C on phosphatidylinositol 4,5-bisphosphate, which is one of the phospholipids that make up the cell membrane. Inositol 1,4,5-trisphosphate is released into the cytoplasm where it releases calcium ions from internal stores within the cell's endoplasmic reticulum. These calcium ions stimulate the activity of B kinase or calmodulin.
A type C phospholipase with specificity towards PHOSPHATIDYLINOSITOLS that contain INOSITOL 1,4,5-TRISPHOSPHATE. Many of the enzymes listed under this classification are involved in intracellular signaling.
A condition in which functional endometrial tissue is present outside the UTERUS. It is often confined to the PELVIS involving the OVARY, the ligaments, cul-de-sac, and the uterovesical peritoneum.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
Agents that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.
A major gonadotropin secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Luteinizing hormone regulates steroid production by the interstitial cells of the TESTIS and the OVARY. The preovulatory LUTEINIZING HORMONE surge in females induces OVULATION, and subsequent LUTEINIZATION of the follicle. LUTEINIZING HORMONE consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH and FSH), but the beta subunit is unique and confers its biological specificity.
Three individuals derived from three FETUSES that were fertilized at or about the same time, developed in the UTERUS simultaneously, and born to the same mother.
Chemical agents that increase the permeability of CELL MEMBRANES to CALCIUM ions.
The period in the MENSTRUAL CYCLE that follows OVULATION, characterized by the development of CORPUS LUTEUM, increase in PROGESTERONE production by the OVARY and secretion by the glandular epithelium of the ENDOMETRIUM. The luteal phase begins with ovulation and ends with the onset of MENSTRUATION.
A plant genus of the family BRASSICACEAE that contains ARABIDOPSIS PROTEINS and MADS DOMAIN PROTEINS. The species A. thaliana is used for experiments in classical plant genetics as well as molecular genetic studies in plant physiology, biochemistry, and development.
The chromosomal constitution of cells which deviate from the normal by the addition or subtraction of CHROMOSOMES, chromosome pairs, or chromosome fragments. In a normally diploid cell (DIPLOIDY) the loss of a chromosome pair is termed nullisomy (symbol: 2N-2), the loss of a single chromosome is MONOSOMY (symbol: 2N-1), the addition of a chromosome pair is tetrasomy (symbol: 2N+2), the addition of a single chromosome is TRISOMY (symbol: 2N+1).
A potent synthetic long-acting agonist of GONADOTROPIN-RELEASING HORMONE with D-tryptophan substitution at residue 6.
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
The unconsolidated mineral or organic matter on the surface of the earth that serves as a natural medium for the growth of land plants.
Wormlike or grublike stage, following the egg in the life cycle of insects, worms, and other metamorphosing animals.
The techniques used to select and/or place only one embryo from FERTILIZATION IN VITRO into the uterine cavity to establish a singleton pregnancy.
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
A polyvinyl polymer of variable molecular weight; used as suspending and dispersing agent and vehicle for pharmaceuticals; also used as blood volume expander.
Experimentation on, or using the organs or tissues from, a human or other mammalian conceptus during the prenatal stage of development that is characterized by rapid morphological changes and the differentiation of basic structures. In humans, this includes the period from the time of fertilization to the end of the eighth week after fertilization.
The material of CHROMOSOMES. It is a complex of DNA; HISTONES; and nonhistone proteins (CHROMOSOMAL PROTEINS, NON-HISTONE) found within the nucleus of a cell.
A plant genus of the family POACEAE that is used for forage.
A class in the phylum MOLLUSCA comprised of mussels; clams; OYSTERS; COCKLES; and SCALLOPS. They are characterized by a bilaterally symmetrical hinged shell and a muscular foot used for burrowing and anchoring.
An ionophorous, polyether antibiotic from Streptomyces chartreusensis. It binds and transports CALCIUM and other divalent cations across membranes and uncouples oxidative phosphorylation while inhibiting ATPase of rat liver mitochondria. The substance is used mostly as a biochemical tool to study the role of divalent cations in various biological systems.
The state or condition of being a human individual accorded moral and/or legal rights. Criteria to be used to determine this status are subject to debate, and range from the requirement of simply being a human organism to such requirements as that the individual be self-aware and capable of rational thought and moral agency.
An ethylmercury-sulfidobenzoate that has been used as a preservative in VACCINES; ANTIVENINS; and OINTMENTS. It was formerly used as a topical antiseptic. It degrades to ethylmercury and thiosalicylate.
A species of nematode that is widely used in biological, biochemical, and genetic studies.
Liquid components of living organisms.
Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.
The hollow thick-walled muscular organ in the female PELVIS. It consists of the fundus (the body) which is the site of EMBRYO IMPLANTATION and FETAL DEVELOPMENT. Beyond the isthmus at the perineal end of fundus, is CERVIX UTERI (the neck) opening into VAGINA. Beyond the isthmi at the upper abdominal end of fundus, are the FALLOPIAN TUBES.

Prolonged mating in prairie voles (Microtus ochrogaster) increases likelihood of ovulation and embryo number. (1/2757)

Prairie voles are induced ovulators that mate frequently in brief bouts over a period of approximately 24 h. We examined 1) impact of mating duration on ovulation and embryo number, 2) incidence of fertilization, 3) temporal pattern of embryo development, 4) embryo progression through the reproductive tract over time, and 5) embryo development in culture. Mating was videotaped to determine first copulation, and the ovaries were examined and the reproductive tracts flushed at 6, 8, 10, 12, 16, 20, and 24 h and 2, 3, and 4 days after first copulation. The number of mature follicles and fresh corpora lutea and the number and developmental stage of embryos were quantified. One, two-, and four-cell embryos were cultured in Whitten's medium. Mature follicles were present at the earliest time examined (6 h). Thirty-eight percent of females that had been paired for < 12 h after the first copulation ovulated, whereas all females paired >/= 12 h after the first copulation ovulated. Virtually all (> 99%) oocytes recovered from females paired for >/= 12 h after first copulation were fertilized. Pairing time after first copulation and mean copulation-bout duration were significant (p < 0.05) determinants of embryo number. Embryos entered the uterine horns and implanted on Days 3 and 4, respectively, after first copulation (Day 0). Embryos cultured in vitro underwent approximately one cell division per day, a rate similar to that in vivo. We conclude that prairie voles ovulate reliably after pairing for >/= 12 h, although some females showed exceptional sensitivity not predicted by the variables quantified. Prolonged mating for longer than 12 h increased the total embryos produced. This mechanism likely has adaptive significance for increasing offspring number.  (+info)

Male gametic cell-specific gene expression in flowering plants. (2/2757)

The role of the male gamete-the sperm cell-in the process of fertilization is to recognize, adhere to, and fuse with the female gamete. These highly specialized functions are expected to be controlled by activation of a unique set of genes. However, male gametic cells traditionally have been regarded as transcriptionally quiescent because of highly condensed chromatin and a very reduced amount of cytoplasm. Here, we provide evidence for male gamete-specific gene expression in flowering plants. We identified and characterized a gene, LGC1, which was shown to be expressed exclusively in the male gametic cells. The gene product of LGC1 was localized at the surface of male gametic cells, suggesting a possible role in sperm-egg interactions. These findings represent an important step toward defining the molecular mechanisms of male gamete development and the cellular processes involved in fertilization of flowering plants.  (+info)

Treatment of mouse oocytes with PI-PLC releases 70-kDa (pI 5) and 35- to 45-kDa (pI 5.5) protein clusters from the egg surface and inhibits sperm-oolemma binding and fusion. (3/2757)

The effect of phosphatidyinositol-specific phospholipase C (PI-PLC) on mouse sperm-egg interaction was investigated in this study to determine if glycosyl-phosphatidylinositol (GPI)-anchored proteins are involved in mammalian fertilization. When both sperm and zona-intact oocytes were pretreated with a highly purified preparation of PI-PLC and coincubated, there was no significant effect on sperm-zona pellucida binding; however, fertilization was reduced from 59.6% (control group) to 2.8% (treatment group). A similar reduction in fertilization rates was found when zona-intact oocytes were treated with PI-PLC and washed prior to incubation with untreated sperm. The effect of PI-PLC on sperm binding and fusion with zona-free oocytes was then investigated. Treatment of sperm with PI-PLC had no significant effect on sperm-egg binding or fusion. However, treatment of eggs with PI-PLC significantly reduced sperm-egg binding and fusion from 6.2 bound and 2.1 fused sperm per egg in the control group to 2.1 bound and 0.02 fused sperm per egg in the treatment group. This decrease in sperm-egg binding and fusion depended on the dose of PI-PLC employed, with a maximal inhibitory effect on binding and fusion at 5 and 1 U/ml, respectively. PI-PLC-treated oocytes could be artificially activated by calcium ionophore, demonstrating that the oocytes were functionally viable following treatment. Furthermore, treatment of oocytes with PI-PLC did not reduce the immunoreactivity of the non-GPI-anchored egg surface integrin, alpha6beta1. Taken together, these observations support the hypothesis that PI-PLC affects fertilization by specifically releasing GPI-anchored proteins from the oolemma. In order to identify the oolemmal GPI-anchored proteins involved in fertilization, egg surface proteins were labeled with sulfo-NHS biotin, treated with PI-PLC, and analyzed by two-dimensional gel electrophoresis followed by avidin blotting. A prominent high-molecular-weight protein cluster (approximately 70 kDa, pI 5) and a lower molecular weight (approximately 35-45 kDa, pI 5.5) protein cluster were released from the oolemmal surface as a result of PI-PLC treatment. It is likely that these GPI-anchored egg surface proteins are required for sperm-egg binding and fusion.  (+info)

Mutations in FIE, a WD polycomb group gene, allow endosperm development without fertilization. (4/2757)

A fundamental problem in biology is to understand how fertilization initiates reproductive development. Higher plant reproduction is unique because two fertilization events are required for sexual reproduction. First, a sperm must fuse with the egg to form an embryo. A second sperm must then fuse with the adjacent central cell nucleus that replicates to form an endosperm, which is the support tissue required for embryo and/or seedling development. Here, we report cloning of the Arabidopsis FERTILIZATION-INDEPENDENT ENDOSPERM (FIE) gene. The FIE protein is a homolog of the WD motif-containing Polycomb proteins from Drosophila and mammals. These proteins function as repressors of homeotic genes. A female gametophyte with a loss-of-function allele of fie undergoes replication of the central cell nucleus and initiates endosperm development without fertilization. These results suggest that the FIE Polycomb protein functions to suppress a critical aspect of early plant reproduction, namely, endosperm development, until fertilization occurs.  (+info)

Activation of Xenopus eggs by proteases: possible involvement of a sperm protease in fertilization. (5/2757)

Egg activation in cross-fertilization between Xenopus eggs and Cynops sperm may be caused by a protease activity against Boc-Gly-Arg-Arg-MCA in the sperm acrosome. To determine the role of the sperm protease in fertilization, the protease was purified from Cynops sperm using several chromatographic techniques. We found that purified sperm protease readily hydrolyzes Boc-Gly-Arg-Arg-MCA and Z-Arg-Arg-MCA, that protease activity was inhibited by the trypsin inhibitors aprotinin and leupeptin, and that not only the purified protease, but also cathepsin B, induces activation in Xenopus eggs. We inseminated unfertilized Xenopus eggs with homologous sperm in the presence of various peptidyl MCA substrates or protease inhibitors and demonstrated that trypsin inhibitors or MCA substrates containing Arg-Arg-MCA reversibly inhibited fertilization of both fully jellied and denuded eggs. Sperm motility was not affected by the reagents. An extract obtained from Xenopus sperm showed hydrolytic activity against Boc-Gly-Arg-Arg-MCA, Z-Arg-Arg-MCA, and Arg-MCA. These results suggest that the tryptic protease in Xenopus sperm is involved in fertilization, most likely by participating in egg activation.  (+info)

Evidence that a starfish egg Src family tyrosine kinase associates with PLC-gamma1 SH2 domains at fertilization. (6/2757)

The initiation of calcium release at fertilization in the eggs of most animals relies on the production of IP3, implicating the activation of phospholipase C. Recent work has demonstrated that injection of PLC-gamma SH2 domain fusion proteins into starfish eggs specifically inhibits the initiation of calcium release in response to sperm, indicating that PLC-gamma is necessary for Ca2+ release at fertilization [Carroll et al. (1997) J. Cell Biol. 138, 1303-1311]. Here we investigate how PLC-gamma may be activated, by using the PLC-gamma SH2 domain fusion protein as an affinity matrix to identify interacting proteins. A tyrosine kinase activity and an egg protein of ca. Mr 58 K that is recognized by an antibody directed against Src family tyrosine kinases associate with PLC-gamma SH2 domains in a fertilization-dependent manner. These associations are detected by 15 s postfertilization, consistent with a function in releasing Ca2+. Calcium ionophore treatment of eggs did not cause association of the kinase activity or of the Src family protein with the PLC-gamma SH2 domains. These data identify an egg Src family tyrosine kinase as a potential upstream regulator of PLC-gamma in the activation of starfish eggs.  (+info)

Na+/H+ antiporter activity in hamster embryos is activated during fertilization. (7/2757)

This study characterized the activation of the regulatory activity of the Na+/H+ antiporter during fertilization of hamster embryos. Hamster oocytes appeared to lack any mechanism for the regulation of intracellular pH in the acid range. Similarly, no Na+/H+ antiporter activity could be detected in embryos that were collected from the reproductive tract between 1 and 5 h post-egg activation (PEA). Activity of the Na+/H+ antiporter was first detected in embryos collected at 5.5 h PEA and gradually increased to reach maximal activity in embryos collected at 7 h PEA. Parthenogenetically activated one-cell and two-cell embryos demonstrate Na+/H+ antiporter activity, indicating that antiporter activity is maternally derived and initiated by activation of the egg. The inability of cycloheximide, colchicine, or cytochalasin D to affect initiation of antiporter activity indicates that antiporter appearance is not dependent on the synthesis of new protein or recruitment of existing protein to the cell membrane. In contrast, incubation of one-cell embryos with sphingosine did inhibit the appearance of Na+/H+ antiporter activity, showing that inhibition of normal protein kinase C activity is detrimental to antiporter function. Furthermore, incubation of oocytes with a phorbol ester which stimulates protein kinase C activity induced Na+/H+ antiporter activity in oocytes in which the activity was previously absent. Incubation with an intracellular calcium chelator also reduced the appearance of antiporter activity. Taken together, these data indicate that the appearance of Na+/H+ antiporter activity following egg activation may be due, at least in part, to regulation by protein kinase C and intracellular calcium levels.  (+info)

Nucleo-cytoplasmic interactions that control nuclear envelope breakdown and entry into mitosis in the sea urchin zygote. (8/2757)

In sea urchin zygotes and mammalian cells nuclear envelope breakdown (NEB) is not driven simply by a rise in cytoplasmic cyclin dependent kinase 1-cyclin B (Cdk1-B) activity; the checkpoint monitoring DNA synthesis can prevent NEB in the face of mitotic levels of Cdk1-B. Using sea urchin zygotes we investigated whether this checkpoint prevents NEB by restricting import of regulatory proteins into the nucleus. We find that cyclin B1-GFP accumulates in nuclei that cannot complete DNA synthesis and do not break down. Thus, this checkpoint limits NEB downstream of both the cytoplasmic activation and nuclear accumulation of Cdk1-B1. In separate experiments we fertilize sea urchin eggs with sperm whose DNA has been covalently cross-linked to inhibit replication. When the pronuclei fuse, the resulting zygote nucleus does not break down for >180 minutes (equivalent to three cell cycles), even though Cdk1-B activity rises to greater than mitotic levels. If pronuclear fusion is prevented, then the female pronucleus breaks down at the normal time (average 68 minutes) and the male pronucleus with cross-linked DNA breaks down 16 minutes later. This male pronucleus has a functional checkpoint because it does not break down for >120 minutes if the female pronucleus is removed just prior to NEB. These results reveal the existence of an activity released by the female pronucleus upon its breakdown, that overrides the checkpoint in the male pronucleus and induces NEB. Microinjecting wheat germ agglutinin into binucleate zygotes reveals that this activity involves molecules that must be actively translocated into the male pronucleus.  (+info)

At fertilization in mammals, the sperm triggers a series of low-frequency cytosolic Ca2+ oscillations that continue for several hours ( Cuthbertson and Cobbold, 1985; Kline and Kline, 1992). This Ca2+ signal is responsible for the exocytosis of cortical granules, resumption of meiosis and activation of development ( Kline and Kline, 1992; Miyazaki et al., 1993; Xu et al., 1994; Abbott and Ducibella, 2001). In mammals, the main intracellular Ca2+ channel involved in Ca2+ release at fertilization is the type I Ins(1,4,5)P3-receptor [Ins(1,4,5)P3R]. It is present far in excess of the other isoforms ( Jellerette et al., 2000; Brind et al., 2000) and injection of functionally inhibitory antibodies or downregulation of the receptor during maturation, both lead to an inhibition of fertilization-induced Ca2+ transients ( Miyazaki et al., 1993; Brind et al., 2000). Thus, Ca2+ release and egg activation at fertilization is triggered by Ins(1,4,5)P3 production.. Ins(1,4,5)P3 is generated via phospholipase ...
At fertilization, the egg must undergo a rise in intracellular Ca 2+ so that embryogenesis may begin. How the sperm signals the egg to release Ca2+ is not well understood. This dissertation examines how the sperm stimulates Ca2+ release in frog and ascidian eggs at fertilization. ^ One secondary messenger used by somatic cells to elicit intracellular Ca2+ release is inositol trisphosphate (IP3). Results from experiments examining Xenopus oocyte maturation indicate that frog oocytes become more sensitive to IP3 as they mature into fertilizable eggs. Because this evidence suggested that IP3 may be important for Xenopus fertilization, frog eggs were injected with an antibody against the IP3 receptor and then inseminated. The inhibitory effect of this antibody on Ca2+ release after insemination indicates that the Ca2+ rise at fertilization in frog eggs requires IP3. ^ Because IP3 is generated by phospholipase C (PLC) enzymes, the role played by PLCs during Xenopus fertilization was investigated. The PLC
Free-spawning marine invertebrates that live near shore or in estuaries may experience reduced fertilization success during low-salinity events. Although several studies have documented reproductive failure at reduced salinity in estuarine animals, few have looked at whether developmental failure is due to a failure of fertilization or to a failure of fertilized eggs to cleave. In this study, we e... read morexamined the effects of salinities ranging from 18 to 32 psu on fertilization success and early development in the sand dollar Echinarachnius parma. In addition to decoupling the effects of low salinity on fertilization from its effects on early cleavage, we also assessed whether eggs or sperm were the weak link in accounting for reproductive failure. We found that both fertilization and cleavage failed at salinities below about 22 psu but that development could be partially rescued by returning zygotes to full-strength seawater. We also found that sperm remained active and capable of ...
Title:Calcium Signaling in Mammalian Eggs at Fertilization. VOLUME: 16 ISSUE: 24. Author(s):Hideki Shirakawa, Takashi Kikuchi and Masahiko Ito. Affiliation:Department of Engineering Science, The University of Electro-Communications Graduate School of Informatics and Engineering, 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585, Japan.. Keywords:Calcium influx, Calcium oscillations, Calcium release, Calcium wave, Egg activation, Fertilization, Fluorescence imaging, Infertility, Inositol 1, 4, 5-trisphosphate, Phospholipase Cζ.. Abstract:The innovation and development of live-cell fluorescence imaging methods have revealed the dynamic aspects of intracellular Ca2+ in a wide variety of cells. The fertilized egg, the very first cell to be a new individual, has long been under extensive investigations utilizing Ca2+ imaging since its early days, and spatiotemporal Ca2+ dynamics and underlying mechanisms of Ca2+ mobilization, as well as physiological roles of Ca2+ at fertilization, have become more or less ...
From Meiosis to Mitosis: The Astonishing Flexibility of Cell Division Mechanisms in Early Mammalian Development (2016)[1] The egg can be arrested in the prophase of meiosis I for decades, and when it is activated, the spindle is assembled de novo. This spindle must function with the highest of fidelity and yet its assembly is unusually achieved in the absence of conventional centrosomes and with minimal influence of chromatin. Moreover, its dramatic asymmetric positioning is achieved through remarkable properties of the actin cytoskeleton to ensure elimination of the polar bodies. The second meiotic arrest marks a uniquely prolonged metaphase eventually interrupted by egg activation at fertilization to complete meiosis and mark a period of preparation of the male and female pronuclear genomes not only for their entry into the mitotic cleavage divisions but also for the imminent prospect of their zygotic expression ...
From Meiosis to Mitosis: The Astonishing Flexibility of Cell Division Mechanisms in Early Mammalian Development (2016)[1] The egg can be arrested in the prophase of meiosis I for decades, and when it is activated, the spindle is assembled de novo. This spindle must function with the highest of fidelity and yet its assembly is unusually achieved in the absence of conventional centrosomes and with minimal influence of chromatin. Moreover, its dramatic asymmetric positioning is achieved through remarkable properties of the actin cytoskeleton to ensure elimination of the polar bodies. The second meiotic arrest marks a uniquely prolonged metaphase eventually interrupted by egg activation at fertilization to complete meiosis and mark a period of preparation of the male and female pronuclear genomes not only for their entry into the mitotic cleavage divisions but also for the imminent prospect of their zygotic expression ...
External fertilization usually occurs in aquatic environments where both eggs and sperm are released into the water. After the sperm reaches the egg, fertilization takes place. Mos
Animal reproductive system - Animal reproductive system - Adaptations for internal fertilization: Fertilization among vertebrates may be external or internal, but internal fertilization is not always correlated with viviparity or the presence of intromittent (copulatory) organs. The latter, uncommon among fishes, amphibians, and birds, are present in all reptiles (except Sphenodon) and mammals. A considerable number of fishes are viviparous; in them, fertilization is internal, and the males have intromittent organs. The claspers of most male elasmobranchs are usually paired extensions of pelvic fins that are inserted into the females uterus for transfer of sperm. The clasper, supported by modified fin cartilages, contains a groove along which sperm are conveyed into the
We have used Thomas-type recessed-tip pH-sensitive microelectrodes to measure the intracellular pH (pHi) in Xenopus eggs during both fertilization and ionophore activation. The average pHi in unfertilized eggs is 7.33 +/- 0.11 (SD; n = 21) with a resting membrane potential of -10.1 +/- 3.5 (SD; n = 38) mV. Within 2 min after the onset of the fertilization potential, there is a slight, transient pHi decrease of 0.03 +/- (SD, n = 8), followed by a distinct, permanent pHi increase of 0.31 +/- 0.11 (SD; n = 7) beginning approximately 10 min after the start of the fertilization potential and becoming complete approximately 1 h later. The pHi remains near this level of 7.67 +/- 0.13 (SD, n = 10) through at least 10 cleavage cycles, but it is possible to discern pHi oscillations with a mean amplitude of 0.03 +/- 0.02 (SD, n = 38). Eggs perfused for at least 2 h in Na+-free solution with 1 mM amiloride exhibited all of these pHi changes, so these changes do not require extracellular Na+. Similar ...
In external fertilization fusion of sperm and egg occurs externally of the female body. External fertilization needs water to facilitate their fertilization, so it occurs in wet environments. Female and male gametes are released to the water, and male gamete is mostly mobile. This type of fertilization can be seen in lower plants. The advantage of external fertilization is that it produces a large number of offspring due to the external hazards. So survival of the embryo is comparatively lower. Amphibians and fish are examples for these types of animals ...
Much of the scientific knowledge on oocyte maturation, fertilization, and embryonic development has come from the experiments using gametes of marine organisms that reproduce by external fertilization. In particular, echinoderm eggs have enabled the study of structural and biochemical changes related to meiotic maturation and fertilization owing to the abundant availability of large and transparent oocytes and eggs. Thus, in vitro studies of oocyte maturation and sperm-induced egg activation in starfish are carried out under experimental conditions that resemble those occurring in nature. During the maturation process, immature oocytes of starfish are released from the prophase of the first meiotic division, and acquire the competence to be fertilized through a highly programmed sequence of morphological and physiological changes at the oocyte surface. In addition, the changes in the cortical and nuclear regions are essential for normal and monospermic fertilization. This review summarizes the current
Much of the scientific knowledge on oocyte maturation, fertilization, and embryonic development has come from the experiments using gametes of marine organisms that reproduce by external fertilization. In particular, echinoderm eggs have enabled the study of structural and biochemical changes related to meiotic maturation and fertilization owing to the abundant availability of large and transparent oocytes and eggs. Thus, in vitro studies of oocyte maturation and sperm-induced egg activation in starfish are carried out under experimental conditions that resemble those occurring in nature. During the maturation process, immature oocytes of starfish are released from the prophase of the first meiotic division, and acquire the competence to be fertilized through a highly programmed sequence of morphological and physiological changes at the oocyte surface. In addition, the changes in the cortical and nuclear regions are essential for normal and monospermic fertilization. This review summarizes the current
The one service that is likely to have the biggest impact on the color and health of your grass, is lawn fertilization. And although is sounds like an easy step, theres more to it than you might think.. Depending on the type of grass you have, soil quality and local growing conditions, youll have a unique set of fertilization needs. With the experts from Ultra Lawn, your lawn will get the right nutrients it needs to thrive.. ​. Fertilization Plans Designed for You. ​. Every lawn requires its own unique fertilization mixture. For those who dont want the hassle of figuring that mixture out, its as easy as calling a company like Ultra Lawn. Our fertilization experts specialize in a variety of grass types. Well tailor a fertilization plan that gives your lawn the proper nutrients on the right schedule, ensuring a lush, green yard.. ​. Why Do I Need to Fertilize my Lawn?. ​. Fertilization is an important part of general lawn care for a few main reasons:. ...
The phylum chordata represents the whole diverse class of vertebrates, animals with a vertebral column, as well as lancelets and tunicates. Two fertilization strategies are employed by members of chordata: internal fertilization, where the gametes, or sperm and egg, meet inside the body of one parent, and external ...
In Vitro Fertilization (IVF) is a method of assisted reproduction in which the mans sperm and the womans egg are combined in a laboratory. Following fertilization and early embryo development in the laboratory, an appropriate number of embryos are transferred to the womans uterus.. Natural conception begins with the release of a single ovum (egg) from the womans ovaries. The fallopian tube picks up the egg, and it is within the fallopian tube that the sperm will fertilize the egg. Following fertilization, the zygote, or early embryo, stays in the tube for about three days while it divides into more and more cells. The embryo is then transported to the uterus where it will float for approximately three days until it implants into the wall of the uterus.. IVF was originally designed for couples in which the womans fallopian tubes were absent or damaged. The events normally occurring in the fallopian tubes, including fertilization and early embryo development, occur in the laboratory ...
The first issue that an egg and a sperm of any organism type face in successfully producing an embryo is the possibility of polyspermy. Polyspermy is the fertilization of an egg by multiple sperm, and the results of such unions are lethal.. If multiple sperm fertilize an egg, the embryo inherits multiple paternal centrioles. This causes competition for extra chromosomes and results in the disruption of the creation of the cleavage furrow, thus causing the zygote to die. As an important model organism in the study of fertilization and embryonic development, polyspermy in sea urchins has been studied in detail. The sea urchins methods of polyspermy prevention have been broken down into two main pathways. These two primary pathways are known as the fast block and the slow block to polyspermy.. Fast Block. After the sperms receptors come into contact with the eggs jelly layer and the acrosomal enzymes are released and break down the jelly layer, the sperm head comes into contact with the ...
i) Endogamy (Self-fertilization): It involves the fusion of two types of gametes derived from the same parent (uni-parental) e.g., Taenia. It is a very rare process. (ii) Exogamy (Cross-fertilization): When two fusing gametes are derived from different parents (biparental) e.g., in cockroach, frog, human beings etc. It is more common. On the basis of structure of fusing gametes, syngamy is of following types: (i) Isogamy: When two fusing gametes are morphologically as well as physiologically similar to each other e.g., in Monocystis (a protozoan). Such gametes are called isogametes. (ii) Anisogamy or Heterogamy: When two fusing gametes are morphologically or physiologically different from each other, e.g., in frog, rabbit, human beings etc. Such gametes are called heterogametes or anisogametes {e.g., microgamete or sperm and macrogamete or ovum). ...
In fertilization, there is the union of sperm and egg which is the mechanism for pollination. Each sperm and egg has half of the hereditary material which unite to develop a new plant. When a pollen grain come in contact, a small tube is generated along with the sperm. This pollen tube gets fit into another pipe-like structure known as the style of the female pistil. This pollen tube expands from the style to the opening of the ovary where the sperms get collected. When the sperm and egg get united completely, the egg fertilizes and develops into a plant seed, which is a zygote. This process of fertilization takes place inside the flowering plants.. Double fertilization is a very distinct process that occurs in the flowering plants also known as angiosperm. In this type of fertilization, out of two sperms, one fertilizes the egg to form the zygote while other sperm combines with the secondary nucleus to form a triploid nucleus. This is also known as the primary endosperm nucleus. Hence in this ...
We have examined whether IP3R1 phosphorylation at the MPM2 epitope, an epitope commonly phosphorylated by M-phase kinases, may underpin the enhanced functional activity of IP3R1 in MII eggs. Our results show that MPM2 IP3R1 phosphorylation is associated with the presence of [Ca2+]i oscillations in mouse eggs and zygotes. Using in vitro assays, we found that MAPK/ERK2 phosphorylates IP3R1 at a conserved consensus site and that MAPK activity is required for in vivo MPM2-detectable IP3R1 phosphorylation. We also observed that abrogation of MPM2 IP3R1 phosphorylation during maturation coincides with the failure of eggs to mount [Ca2+]i oscillations. These results establish an unmistakable molecular link between the cell cycle and the Ca2+ releasing machinery.. The role of Ca2+ at fertilization represents, perhaps, the clearest manifestation of cell-cycle regulation by a second messenger, as a sperm-induced Ca2+ response is required to induce cell-cycle progression in all species studied to date ...
Natural and in vitro fertilisation. Computer artwork of the female reproductive system, showing normal internal fertilisation (left) and in vitro fertilisation (IVF, right). Normally an ovum (egg, orange), released (ovulation) by one of the ovaries (yellowish, upper left and right), is fertilised by a sperm (blue, upper left) and passes along the fallopian tube to the uterus (centre), where it implants in the uterine lining and develops into a foetus. With IVF the sperm nucleus (blue, upper right) is combined with the egg cell in a lab and the resultant embryo is manually introduced to the uterus, where it will develop in the same way. - Stock Image C009/5898
The phase of elevated metabolic activity, during which oxygen consumption increases, that occurs at fertilization. An enhanced uptake of oxygen leads to the production of hydrogen peroxide (H2O2), superoxide anions and hydroxyl radicals. Capacitation, a necessary prerequisite event to successful fertilization, can be induced by reactive oxygen species in vitro; hydrogen peroxide is used as an extracellular oxidant to cross-link the protective surface envelopes. (3 ...
Guides you through the decision to have a procedure to fix a tubal problem or to have in vitro fertilization. Looks at chances of pregnancy and risks after each procedure. Includes interactive tool to help you make your decision.
A now large body of function has solidified the central function that mitochondria play in oocyte advancement, fertilization, and embryogenesis. three different sites with a complete of 104 sufferers indicated an advantage of the task for improving being pregnant achievement rates, using the delivery of kids conceived through the inclusion of autologous germline mitochondrial energy transfer during fertilization. Nevertheless, a fourth scientific research, comprising 57 patients, didnt show an advantage of autologous germline mitochondrial energy transferCfertilization fertilization by itself for enhancing cumulative live delivery rates. Complicating this specific section of function further, a recently available mouse research, which claimed to check the long-term protection of autologous mitochondrial supplementation during fertilization, elevated concerns over the usage of the task for reproduction. Nevertheless, autologous mitochondria werent useful for preclinical testing within this ...
Fertilization is one of the most fundamental processes in nature, yet critical gaps exist in our understanding of this essential process. One of the earliest an...
You are looking at a never-before witnessed event: the explosion of chemical activity inside a newly-fertilised egg that marks the very first moment of life. Professor Michael Whitaker and colleagues at the Newcastle University Medical School, UK, have used special dyes and confocal light microscopy to allow calcium ions, which are normally invisible, to be seen for the first time. - 48 per page (session default)
by Katherine L. Wozniak, Rachel E. Bainbridge, Dominique W. Summerville, Maiwase Tembo, Wesley A. Phelps, Monica L. Sauer, Bennett W. Wisner, Madelyn E. Czekalski, Srikavya Pasumarthy, Meghan L. Hanson, Melania B. Linderman, Catherine H. Luu, Madison E. Boehm, Steven M. Sanders, Katherine M. Buckley, Daniel J. Bain, Matthew L. Nicotra, Miler T. Lee, Anne E. Carlson. One of the earliest and most prevalent barriers to successful reproduction is polyspermy, or fertilization of an egg by multiple sperm. To prevent these supernumerary fertilizations, eggs have evolved multiple mechanisms. It has recently been proposed that zinc released by mammalian eggs at fertilization may block additional sperm from entering. Here, we demonstrate that eggs from amphibia and teleost fish also release zinc. Using Xenopus laevis as a model, we document that zinc reversibly blocks fertilization. Finally, we demonstrate that extracellular zinc similarly disrupts early embryonic development in eggs from diverse phyla, ...
Neoglycoproteins with N-acetylglucosamine residues (BSA-GlcNAc) induced specifically the acrosome reaction (AR) in human spermatozoa. Our objective was to investigate the relationship between this phenomenon and the invitro fertilization (IVF) rate. Sperm suspensions from IVF protocols were incubated with BSA-GlcNAc (t), using calcium ionophore (i) or medium alone (c) as positive or negative controls. When the normalized AR percentage ratio (STIM) (% ARt-%ARc):(%ARi-%ARc) was compared with fertilization rate in 31 couples from our IVF programme, a positive correlation was found (r = 0.46, P , 0.01). The fertilization rate in patients with STIM , or = 0.2 was higher than in non-responders (STIM , 0.2); 72 +/- 7% compared with 5 +/- 3%. The overall predictive value of this test for adequate fertilization rate (, 30%) was 87%, sensitivity 91% and specificity 78%. False positives were 9% and false negatives 22%. For successful fertilization rates (, 60%), the results were: overall predictive value, ...
Biology Assignment Help, Barriers to fertilisation, Barriers to Fertilisation Incompatibility can occur anywhere from pollination to syngamy and consequently obstructing fertilisation. The pollen fails to germinate or the pollen tube is inhibited to penetrate the stigma. The progamic barriers
Fish in the genus Limia are lecithotrophic, meaning that there is pre-fertilization maternal provisioning in the form of yolked eggs ... Fertilization is achieved internally with the males gonopodium, a modified anal fin used for sperm transfer ... of the asymmetrical energy costs associated with internal fertilization, females in many Poeciliid species act as the choosy sex, with males exhibiting ornate coloration and morphology as well as elaborate courtship ...
The major goal of turf fertilization is to produce attractive turf that is healthy, and able to withstand the rigors of its intended use. Fertilization is one of the most basic and important components of a turf management program.. Turf fertilization contributes greatly to lawn color, density, uniformity, and growth. Properly fertilized grass can compete with weeds and is able recover from damage caused by environmental stresses faster than improperly fertilized lawns.. ...
Occasionally a pro-choice person will give me a link to an article attempting to refute the idea that a new human organism begins to exist when the process of conception is successfully completed. There is ample scientific evidence for that statement, and that evidence can be found here.. The article The unscientific nature of the concept that human life begins at fertilization, and why it matters (by Richard J. Paulson, M.D.) was recently sent to me by someone and Id like to address what is being said in the article. This response turned out to be a lot longer than I expected, but that is likely due to the number of assumptions Dr. Paulson infused into his statements, without reasonable justification. So a lot had to be unpacked.. The first two paragraphs express reasonable concerns about misinformation and disinformation. The author then proceeds to unironically provide ideologically-motivated misinformation, disguising his conclusions behind the objectivity of science. As Dr. John Lennox ...
Practicums.. 195. Study of The Spike Of Wheat.-Request each student to report the following, after examining a head of wheat:. 1. Number of spikelets in the spike of wheat.. 2. Number of flowers in each spikelet. 3. Number of grains in the whole spike.. 4. Determine the number and arrange weight of grains occupying first, second,. third and fourth place from rachis.. 5. Number of empty glumes in a spikelet.. 6. Make a sketch of the beak, shoulder and auricle of the empty glume.. 7. How does the flowering glume differ from the palea?. 8. How is the spikelet attached to the rachis?. 9. Draw the rachis.. The spikes of wheat should be laid between pieces of moistened blotting paper for several hours before handing the students, in order to toughen the parts.. 196. Method Of Cross-fertilization.-In order to effect cross-fertilization, the anthers must be removed from all the flowers on the. spike, before any of them have shed their pollen. This can best be done when or before the anthers are slightly ...
Fertilization is the process by which male and female gametes are fused together, initiating the development of a new organism. The male gamete or sperm, and the female gamete, egg or ovum are specialized sex cells, which fuse together to begin the formation of a zygote during a process called sexual reproduction.
View Notes - RNAProtein160-page16 from BIO 151 at SUNY Stony Brook. This results in part of the DNA being "backwards" and unreadable. Many gametes are not viable after inversions. Gene
Pregnancy: From Fertilization to Birth. BC Science Probe 9 Section 4.3 Pages 117-121. Pregnancy. So females produce eggs and males produce sperm… but how does the rest happen?. Fertilization. During sexual intercourse, millions of sperm are released into the vagina. Slideshow 2177940 by...
In mammals, fertilization takes place in a protected and well-controlled environment within the oviduct. Due to the obvious difficulty of studying fertilization in situ, in vitrofertilization...
View Notes - Ch 28 Pregnancy & Development from BIOL 1141 at UMSL. CH. 28 : Pr e gna nc y a n d Hum a n Dev e l op m e n t I. From Egg to Embryo A. Fertilization 1. Fertilization occurs when a
Fertilization changes the structure and function of the cell surface. In sea urchins, these changes include polymerization of cortical actin and a coincident, switch-like increase in the activity of the multidrug efflux transporter ABCB1a. However, it is not clear how cortical reorganization leads t …
The effect of immunization against oestradiol-17â (E2) on fertilization rates and of human chorionic gonadotrophin (hCG) in reducing the proportion
Greenup offers professional tree fertilization. Trees, like all living plants, have many nutritional requirements for sustained growth and reproduction. When one or more of these nutrients are deficient in the soil, the tree will not reach its full landscape potential, will be more susceptible to disease and insect problems, and will have a shorter life than a similar, well-fertilized tree. ...
If in fact the hydrolysis of PIP2 is taking place at fertilization, then DAG, the other by-product of this process, should also show a demonstrable increase. In 1997, Stith et al. used a DAG mass assay to demonstrate that this was in fact the case. Interestingly, DAG increased more than IP3, revealing that other sources of DAG are present in addition to PIP2 hydrolysis, and suggesting a greater role in fertilization for this secondary messenger.. Direction of IP3 Research. Since there is still much to be understood in the pathway leading to the fertilization wave and the role that IP3 plays in this pathway, research is ongoing. One direction being pursued was first suggested during the 1993 investigation by Nuccitelli et al. They observed small, local increases in [Ca2+]i following sperm-induced activation in eggs which had been pre-injected with heparin, a blocker of IP3 induced calcium release. When eggs were treated with approximately half of the dose of heparin needed to block fertilization ...
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Today, temperatures finally began to climb out of the negatives. With the onset of warmer weather, (using this term gently) I felt it was a good time to start looking towards spring. Over the last few months there have been several inquiries regarding lawn fertilization. In response, I have revised the Iowa State University home lawn fertilization publication. Although you
© Cambridge University Press 2013. Introduction: Sexual reproduction is a survival strategy employed by species for procreation, and is characterized by the transfer of haploid genetic material from each parent to produce diploid offspring, ensuring continued genetic diversity. In mammals, males produce vast numbers of gametes called sperm in the testes (˜53-55µm in length), which are deposited in the female reproductive tract in a liquid medium (semen) via the process of ejaculation. Females produce much larger gametes, eggs (˜100µm in diameter), which are surrounded by a thin glycoprotein layer, the zona pellucida (ZP), and generated in follicles contained in the ovaries which, following maturation, are released and transported through the fallopian tube to the uterus. Sexual reproduction involves the concerted release of these two components, which subsequently fuse to re-form the diploid chromosome number, resulting in a new, genetically unique individual, a process termed fertilization.
UMass Medical School Professor Oliver J. Rando, M.D., Ph.D., sheds new light on the processes of fertilization and epigenetic inheritance in mammals.
(Medical Xpress)-Stanford University School of Medicine researchers have devised a two-part approach to identify developing human embryos most likely to result in successful pregnancies. The technique could transform the ...
This Order brings into force on 6th April 2010 the remaining provisions of the Human Fertilisation and Embryology Act 2008 (the 2008 Act) so far as they are not already in force by virtue of the Human Fertilisation and Embryology Act 2008 (Commencement No.1 and Transitional Provisions) Order 2009(2) and the Human Fertilisation and Embryology Act 2008 (Commencement No.2 and Transitional Provision) and (Commencement No.1 Amendment) Order 2009(3).. This Order brings into force section 54 of the 2008 Act, which makes new provision to enable parental orders to be granted not only to married couples but also to civil partners and two persons living as partners in an enduring family relationship, provided certain conditions are met. The current provision for parental orders in section 30 of the Human Fertilisation and Embryology Act 1990 (the 1990 Act) is repealed by this Order, although Orders made before 6th April 2010 under section 30 will remain valid. This Order also brings into force ...
Our understanding of postcopulatory sexual selection has been constrained by an inability to discriminate competing sperm of different males, coupled with challenges of directly observing live sperm inside the female reproductive tract. Real-time and spatiotemporal analyses of sperm movement, storage, and use within female Drosophila melanogaster inseminated by two transgenic males with, respectively, green and red sperm heads allowed us to unambiguously discriminate among hypothesized mechanisms underlying sperm precedence, including physical displacement and incapacitation of resident sperm by second males, female ejection of sperm, and biased use of competing sperm for fertilization. We find that competitive male fertilization success derives from a multivariate process involving ejaculate-female and ejaculate-ejaculate interactions, as well as complex sperm behavior in vivo.. ...
Human In Vitro Fertilization A Review of the Ethical. Ethical Question: Is In-Vitro Fertilization an ethical way to have a child? Definition: fertilization of an egg in a laboratory dish or test tube; specifically : fertilization by mixing sperm with eggs surgically removed from an ovary followed by uterine implantation of one or more of the resulting fertilized eggs, What most don’t know is that whenever an IVF procedure occurs, a doctor will generate more than just the desired number of embryos. This is where the moral problems begin, especially for Christians.. In vitro fertilization (IVF) is the process of assisted fertilization. The primary advantage, of course, is being able to conceive despite medical conditions which prevent it through natural means or other causes of infertility. Egg are fertilized in a laboratory setting and implanted in the woman. regarding salient ethical issues relating to the practice of in-vitro fertilisation (IVF) in Nigeria. A think-tank session A ...
At fertilisation of mammalian and ascidian eggs the sperm induces a series of Ca²⁺ oscillations. These Ca²⁺ oscillations are triggered by a sperm-borne Ca²⁺-releasing factor whose identity is still unresolved. In both mammals and ascidians Ca²⁺ oscillations in eggs are associated with the period leading up to exit from meiosis and entry into the first embryonic cell cycle. Thus, in mammals Ca²⁺ oscillations continue for several hours but are complete by within 30 min in the ascidian. In mammals and ascidians Ca²⁺ oscillations stop at around the time when pronuclei form in the 1-cell embryo. There is evidence to show that cell cycle factors are important in regulating the fertilisation Ca²⁺ signal. If the formation of pronuclei is blocked either in mammals (by spindle disruption) or in ascidians (by clamping maturation promoting factor levels high) then Ca²⁺ oscillations continue indefinitely. Here, we explore the nature of the sperm Ca²⁺-releasing factor and examine ...
An egg changes dramatically at fertilization. These changes include its developmental potential, its physiology, its gene expression profile, and its cell surface. This review highlights the changes in the cell surface of the egg that occur in response to sperm. These changes include modifications to the extracellular matrix, to the plasma membrane, and to the secretory vesicles whose contents direct many of these events. In some species, these changes occur within minutes of fertilization, and are sufficiently dramatic so that they can be seen by the light microscope. Many of these morphological changes were documented in remarkable detail early in the 1900s by Ernest Everett Just. A recent conference in honor of his contributions stimulated this overview. We highlight the major cell surface changes that occur in echinoderms, one of Justs preferred research organisms. Mol. Reprod. Dev. 76: 942-953, 2009. © 2009 Wiley-Liss, Inc. ...
The physiological processes in loblolly pine leading to enhanced growth in response to fertilization have not been clearly established. We tracked net photosynthesis (Pn), height, basal diameter, and volume changes in loblolly pine seedlings in response to fertilization during the entire 2004 growing season. Pn measurements were conducted prior to fertilization and after fertilization in early May. The seedlings that received fertilization showed an increase in Pn rates above the controls for most of the growing season. Also, the fertilized seedlings had height, basal diameter, and volume increases of 10, 13, and 34 percent over the unfertilized seedlings. We conclude that fertilization led to an initial increase in Pn rates, which helped create extra photoassimilate to be used in building larger leaf areas, which in turn led to more above ground biomass.. ...
Looking for online definition of fertilization in the Medical Dictionary? fertilization explanation free. What is fertilization? Meaning of fertilization medical term. What does fertilization mean?
The majority of MPs voted to allow mitochondrial donation in humans with the aim of enabling an individual to be born without inheriting mitochondrial disease from their mother. The process of mitochondrial donation takes place in conjunction with the fertilisation of an egg by sperm outside of the body. A structure containing nuclear DNA from one egg cell or zygote is transferred to another. The result is an embryo containing DNA derived from three different individuals. Under the regulations, and the Human Fertilisation and Embryology Act 1990, the process would be regulated by the Human Fertilisation and Embryology Authority. The motion supported by the majority of MPs taking part in this vote was: ...
Facing trouble conceiving? 3 Reasons you should consider IVF (In Vitro Fertilisation). Dr. Sharda Jain. FIMSA, FICOG, MNAMS (Obstetrics Gynaecology) , MD - Obstetrics Gynaecology, MBBS · Gynaecologist ·. Facing trouble conceiving? 3 Reasons you should consider IVF (In Vitro Fertilisation). In vitro fertilization (IVF) is a medical procedure that side-steps the sexual act of conceiving and helps infertile couples, conceive a biological child. It involves the manual process of fertilization by combining an egg and sperm in the laboratory and then implanting the embryo into the female to impregnate her.. The inability to give birth through the natural way is caused due to complications like: blocked fallopian tubes, unexplained infertility, polycystic ovary syndrome or PCOS, endometriosis: where parts of the womb lining grow out of the womb, premature ovarian failure and so on.. If you or your partner is having trouble conceiving, you should opt for in vitro fertilization. It holds benefits ...
The global in vitro fertilization (IVF) hormones market is segmented into types such as follicle-stimulating hormone/ gonadotropin-releasing hormone (GnRH) and luteinizing hormone. Among these segments, follicle-stimulating hormone/ gonadotropin-releasing hormone (GnRH) segment is expected to occupy top position in overall in vitro fertilization (IVF) hormones market during the forecast period. Factors such as rising number of infertility cases, increasing awareness about infertility treatment, growth in per capita income of the population are expected to augment the growth of in vitro fertilization (IVF) hormones market.. Global in vitro fertilization (IVF) hormones market is expected to flourish at a CAGR of 10.1% over the forecast period. Moreover, the global in vitro fertilization (IVF) hormones market is anticipated to garner USD 7,571.2 Million by the end of 2021. Increasing number of infertility clinics across the globe and growing cases of infertility are some of the major factors behind ...
Fertilization is a general feature of sexual reproduction in eukaryotic organisms. Its purpose is to restore a diploid genome by means of the fusion of two haploid genomes. In most animals and fucoid algae, polyspermy block occurs at the plasmogamy step. Because the polyspermy barrier in animals and in fucoid algae is incomplete, polyspermic zygotes can be generated by multiple fertilization events. However, these polyspermic zygotes bearing extra centrioles from multiple sperms show aberrant nuclear and cell division, and often die. In contrast to the case in animals and fucoid algae, polyspermic zygotes formed in angiosperms are not expected to die because angiosperms lack centrosomes. In angiosperms, the sporophytic generation is initiated by double fertilization to form seeds. In double fertilization, one sperm cell from the pollen grain fuses with the egg cell, and the resultant zygote develops into an embryo that can transmit genetic material from the parents to the next generation. The ...
Fertilization tubules in wild-type (A) and ida5 (B) mt+ gametes produced in response to a 1-h exposure to 10 mM dibutyryl-cAMP and 1 mM IBMX. Bar, 0.3 μm.
In previous studies, we have found that negatively charged, but not uncharged, amino acids and sugars block sea urchin fertilization. These studies were developed from modeling work in non-living systems using derivatized agarose beads that suggested that charge-charge bonding may control at least some adhesive interactions. In the present study, the effects of positively charged, negatively charged and uncharged molecules were examined in the sea urchin sperm-egg system in over 300 individual trials. The results indicate that depending on the specific molecules utilized, both sperm and egg are exquisitely sensitive to charged but not uncharged molecules and to pH changes in sea water caused by some of the charged molecules. It is shown that egg activation, as well as sperm motility and sperm-egg interactions, can be affected by charged molecules. One compound, fructose-1-phosphate blocked fertilization in S. purpuratus sea urchins but not in Lytechinus pictus sea urchins. These findings ...
There are women all over the world who are not able to naturally conceive children. These women have traditionally been told that they do not have many options outside of adoption, that is, until the development of IVF, or in-vitro fertilization. In-vitro fertilization is a medical procedure that fertilizes an egg in a test tube prior to implanting it in a uterus, which drastically increases the likelihood of a woman bearing one or multiple children. Since then, further technological advances have been made in IVF treatment to now include three parents.. Three-parent in-vitro fertilization involves a range of techniques that are utilized by couples who seek to lower their potential childs risk of genetic mitochondrial disease. Mitochondrial diseases take the lives of many children who are not able to sustain their heart beat. The use of additional DNA from another donor helps lower or potentially eliminate the genetic disease. The Human Fertilization and Embryology Authority in the United ...
In an In Vitro Fertilization (IVF) cycle super ovulating drugs (gonadotropins) are usually taken to stimulate the ovaries to produce more than one egg. In Vitro Fertilization protocols are constantly under review in order to improve the recruitment of the follicles, which contain the eggs, whilst minimizing the doses of gonadotrophins required, with the ultimate aim of increasing the live birth rate.. The addition of growth hormone, which is a biological hormone that can be synthetically produced, as a supplement to gonadotrophins in an In Vitro Fertilization cycle has been suggested as a way in which In Vitro Fertilization pregnancy rates may be increased.Growth hormone has been shown, in animal and human studies, to be important in the recruitment of follicles.However, to date, only a limited number of clinical studies have been performed in order to assess whether the addition of growth hormone can improve the probability of pregnancy in women undergoing ovarian stimulation for In Vitro ...
Double fertilization is a defining feature of flowering plants and involves two nonmotile male gametes (sperm cells) and two female gametes (egg cell and central cell). Both fertilization events are necessary for reproductive success. It is not clear how flowering plants ensure the reliable and on-time fusion of the two pairs of gametes while preventing polyspermy. Sprunck et al. (see the Perspective by Snell) now show that gamete interactions in Arabidopsis depend on small cysteine-rich EC1 proteins that accumulate in storage vesicles of the egg cell and that are released during sperm-egg interaction. EC1 peptides trigger the delivery of a fusogen to the sperm cell surface. An intercellular link connects the two sperm cells throughout the gamete fusion process and could play a role in preventing the spontaneous fusion of activated sperm cells.. S. Sprunck, S. Rademacher, F. Vogler, J. Gheyselinck, U. Grossniklaus, T. Dresselhaus, Egg cell-secreted EC1 triggers sperm cell activation during ...
The eggs of most or all animals are thought to be activated after fertilization by a transient increase in free cytosolic Ca2+ concentration ([Ca2+]i). We have applied Ca2+-selective microelectrodes to detect such an increase in fertilized eggs of the frog, Xenopus laevis. As observed with an electrode in the animal hemisphere, [Ca2+]i increased from 0.4 to 1.2 microM over the course of 2 min after fertilization, and returned to its original value during the next 10 min. No further changes in [Ca2+]i were detected through the first cleavage division. In eggs impaled with two Ca2+ electrodes, the Ca2+ pulse was observed to travel as a wave from the animal to the vegetal hemisphere, propagating at a rate of approximately 10 microns/s across the animal hemisphere. The apparent delay between the start of the fertilization potential and initiation of the Ca2+ wave at the sperm entry site as approximately 1 min. Through these observations describe only the behavior of subcortical [Ca2+]i, we suggest ...
I had ER yesterday. 6 eggs were mature and fertilization attempt was made with ICSI. Only 2 of the eggs fertilized. I was told that typically 80% of the eggs will fertilize using ICSI. So only 33% of my eggs fertilized. Has anyone else had low fertilization rates with ICSI? I was told this is pretty rare. Has anyone had pregnancy success with such a low fertilization rate? Im sad and freaking out! Any stories would be greatly appreciated ...
In-Vitro Fertilization Market Size - USD 15.87 Billion in 2019, IVF Market Growth - CAGR of 9.1%, In-Vitro Fertilization Industry Trends- High demand from developing nations.. The global In-Vitro Fertilization Market is forecasted to reach USD 31.97 Billion by 2027, according to a new report by Emergen Research. The sector is guided by rising infertility occurrences attributable to behavioral improvements, policy measures to have fair insurance schemes, and ongoing efforts by suppliers to the industry. Expansion of fertility therapies to treat male infertility, such as ICSI, is expected shortly to have a positive impact on the rise. In turn, the provision of genomic testing to deter genetic disorder transfer through in-vitro fertilization (IVF) usage is also projected to push the IVF industry. Request a sample copy of the report @ Further key findings from the report suggest. ...
In-Vitro Fertilization Market Size - USD 15.87 Billion in 2019, IVF Market Growth - CAGR of 9.1%, In-Vitro Fertilization Industry Trends- High demand from developing nations.. The global In-Vitro Fertilization Market is forecasted to reach USD 31.97 Billion by 2027, according to a new report by Emergen Research. The sector is guided by rising infertility occurrences attributable to behavioral improvements, policy measures to have fair insurance schemes, and ongoing efforts by suppliers to the industry. Expansion of fertility therapies to treat male infertility, such as ICSI, is expected shortly to have a positive impact on the rise. In turn, the provision of genomic testing to deter genetic disorder transfer through in-vitro fertilization (IVF) usage is also projected to push the IVF industry. Request a sample copy of the report @ Further key findings from the report suggest. ...
Hra - Nursery Fertilization Experiment. Enjoy this big compilation of nice made illustrations about a girl who gets penetrated and fucked in any possible way. All this is a huge experiment - it means that theres a scientific explanation for this :)
In Vitro Fertilization (literally, fertilization in glass) is a procedure during which the egg, instead of being fertilized in the womans fallopian tube, is fertilized in a test tube or petri dish. When minimal sperm is available, frequently ICSI - intracytoplasmic sperm injection - is performed.
In Vitro Fertilization (literally, fertilization in glass) is a procedure during which the egg, instead of being fertilized in the womans fallopian tube, is fertilized in a test tube or petri dish. When minimal sperm is available, frequently ICSI - intracytoplasmic sperm injection - is performed.
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In vitro fertilization is an assisted reproductive technology (ART), which involves retrieving eggs from a womans ovaries and fertilizing them with sperm in vitro. The process involves stimulating a womans ovulatory, removing an ovum from the womans ovaries, and letting sperm fertilize them in a liquid in a laboratory. IVF is one of the widely used treatments to assist couples with infertility issues, which is a key factor that drives the growth of the In-vitro fertilization Market globally.. Request For Sample Copy of This Report: As the trend of new generation women who choose to hire for marriage and pregnancy increases, the marriage is delayed and will lead the In-vitro fertilization Market with pregnant women. In addition, from rural to urban, lifestyle fluctuations, obesity and an increase in disposable income worldwide are one of the key indicators of global market growth.. Major industry participants in the global In-vitro ... Practical Manual of In Vitro Fertilization [4172373] - This practical volume provides a complete review of the most well-established and current diagnostic and treatment techniques comprising in vitro fertilization. Each chapter includes a brief abstract, a keyword glossary, a step-by-step protocol of the laboratory procedures, and expert commentary.The Practical Manual of In Vitro Fertilization: Advanced Methods and Novel
A long-term experiment was conducted to evaluate phosphorus (P) fertilization strategies for alfalfa grown for hay and followed by corn harvested for grain.Alfalfa has greater P requirements than corn, and this is recognized in the ISU Extension publication PM-1688. The guidelines are based on previous research with pure alfalfa or alfalfa-grass mixtures. The information available is about 30 years old; however, there is insufficient information about alternative strategies for distributing P fertilization rates during the alfalfa crop years and for a following corn crop. This study evaluated several combinations of initial and top-dressed P fertilization rates for alfalfa and also evaluated effects of starter P and nitrogen (N) on corn following alfalfa.
On the same day in which the mature eggs are retrieved (Egg Retrieval- (2)), the male partner has to produce a semen sample (Semen Sample Collection - (3)), although the procedure can be done with frozen sperm as well. The sample is subsequently processed in order to dispose of any cell debris or non-functional sperm cells and concentrated in order to increase the number of sperm introduced into the uterus.. Once the egg cells are isolated and the semen sample is processed, they are both transferred into a special type of Petri dish, to allow in vitro fertilization - IVF (In-vitro Fertilization - (4)). The fertilized oocytes (embryos) are grown in carefully controlled laboratory conditions until they are ready to be transferred into the female patients uterus (Embryo Transfer - (5)). During their development in the laboratory (day 2 - day 6), the embryos are monitored and their development is evaluated daily in order to select the highest quality embryos for transfer. All remaining ...
Rational Fertilization is one of the most challenging topics in Precision Agriculture.. Quinta da Cholda uses as a method of calculating fertilization needs, a combination of two methods. First, the average level of export of nutrients based on the average yield of the field. Secondly, the results from the analyses of the soil before the seeding.. In both cases, the applications were the result of an average value within the field. As our fields are very heterogeneous, and the productions vary greatly within the same field, we believe that we have made many mistakes in terms of the real needs of the crops due to that spatial variability of the fields.. As such, we have been developing a new method of determining the real needs of fertilization. In 2018, weve selected several points to collect soil samples based on the apparent electroconductivity variability of the soil. Fertilizer applications (Phosphorus and Potassium) were made with a VRT implement to meet the needs detected in the soil ...
Reproductive System of the Copperhead Snake. The reproductive system of the copperhead is very similar in structure and function to the various other classes, with the exception of the hemipenes, which is analogous to the phallus in the Canvasback Duck and the penis in other taxa. The testes are usually adjacent to each other, and the right one is located more anteriorly in snakes. The testes are where the sperm originates; from there it is expelled into the epididymis, and then carried through the vas deferens that run to the cloaca. From the cloaca the sperm enter the hemipenes, which protrude through the cloaca (Zug et al 2001). The cloaca is present in most primitive gnathostomes and persists in embryos of almost all vertebrates. For this reason the cloaca in reptiles as well as birds seems to be a primitive vertebrate feature. External fertilization seems to be most common in early vertebrates, while internal fertilization using an intermittent organ such as the hemepenes in the copperhead ...
TOPEKA - Kansas Gov. Sam Brownback signed sweeping anti-abortion legislation Friday, giving his state a new law to block tax breaks for abortion providers, ban sex-selection abortions and declare that life begins at fertilization.. Many provisions take effect in July, though the tax changes will be effective for 2014. The measure cleared the Republican-dominated Legislature by wide margins earlier this month.. The GOP governor is a strong abortion opponent who urged lawmakers to create a culture of life after taking office in January 2011.. All human life is sacred. Its beautiful, Brownback said just before signing the measure, flanked by abortion opponents. With this, we continue to build this culture of life in our state.. An Associated Press photo taken before the signing shows a page of notes about the bill on Brownbacks desk that included a handwritten message at the top: JESUS + Mary. Further down the page were typewritten notes spelling out Brownbacks belief that the bill ...
PURPOSE: This project was to determine whether oocytes isolated from virgin aged mice, up to 18 months old, are competent to undergo cytoplasmic maturation in vitro and undergo fertilization and embryonic development. If so, oocyte maturation in vitro could be used as a strategy to rescue valuable genetic resources. RESULTS: Although the number of oocytes recovered from mice was greatly reduced with increasing age, the percentage of oocytes that underwent fertilization, cleavage, and development to the blastocyst stage was essentially unchanged up to 18 months of age. The success of cleavage to the two-cell stage was greater after maturation in vitro (81%) than gonadotropin-induced maturation in vivo (55%). About 20% (20/106) of the embryos derived from oocytes isolated from 18-month-old mice developed to term after embryo transfer. CONCLUSION: Oocytes from virgin aged mice undergo normal cytoplasmic maturation in vitro. Higher percentages of oocytes from aged mice cleave to the two-cell
That movement of the head is created by a vibration of the stiff anterior portion of the tail, generated by the thrashing movement of the posterior segment remaining outside the zona. 26 Chapter1 oscillations limited scythe-like movement may create a shear-thinning effect on the zona that maximizes the effectiveness of that thrust. In accord with the inference that the movement required for zona penetration generates shear forces at the sperm surface, the inner acrosomal membrane has developed an unusual stability which is inappropriate to a fusogenic role. It is possible that in at least some marsupials complete maturation and oocyte fertilizability are reached after ovulation, following the oocytes arrival in the oviduct (see Chapter 7). Furthermore, in all of the three marsupial genera examined, a loss of the cumulus oophorus from around the egg begins some hours before and is complete at ovulation. This stands in contrast to the eutherian situation, where a full cumulus invests the oocyte ...
Here you can browse the debates in the House of Commons Public Bill Committee on the Human Fertilisation and Embryology Bill [Lords ...
The Allen Lab started in 2012 in the Department of Biology at Howard University. The goal of our lab is to study the mechanisms by which a high quality gamete (the egg) is generated and how that gamete then undergoes one of the most fascinating processes in development, fertilization. We use the nematode C. elegans as a model system to study oocyte meiotic maturation, meiotic cell cycle regulation, fertilization and early embryonic development. ...
Phorbol ester (PMA) in concentration 5 and 10ng ml−1 blocks cytokinesis of the second maturation division in mouse oocytes. Karyokinesis is not impaired and digynic triploid oocytes are obtained which undergo first cleavage division.. Effectiveness of blocking cytokinesis is dependent on the timing of exposure of oocytes to PMA action. When oocytes are subjected to PMA at the onset of the second maturation division only 14·5% of eggs are triploid. PMA present during fertilization in vitro (about 1 h exposure to PMA) induces triploidy in 40% eggs. Extending the time of exposure of oocytes to 2 h produces 76% tripronucleate eggs.. Applicability of PMA is compared with the use of cytochalasin B to induce triploidy in the mouse.. ...
Intracytoplasmic spermatozoon injection (ICSI). Artificial insemination (AI). AI - is an introduction of spermatozoa to uterus cavity in the period of spontaneous or induced ovulation. Previously, the sperm (of spouse or donor) is exposed to the special processing, which increases the spermatozoa ability for fertilization. The important condition is an existence of information about uterine tubes passability.. IVF. Fertilization by IVF method includes some consecutive stages. It is controlled ovulation stimulation (COS) during which the woman receives injections with follicle stimulating preparations. Then, with intravenous anesthesia, the transvaginal puncture of follicles (TVP) is made. All received oocytes (ova) are impregnated by sperm of the husband (donor) in the conditions of embryological laboratory. In the course of cultivation of embryos, in the incubator the conditions, which are most approached to that like in the womans organism, are created. Further, the choice of one or two most ...
how in vitro fertilization works. ivf now fastest way to get pregnant,when you get exhausted with all the other ways of trying to get pregnant,then probably ivf is the next step suggested by the infertility specialists.what is ivf?in the process of in vitro fertilization (ivf),eggs and sperm are br
Oogamy is seen to be the evolutionary step that led to internal fertilization, in response to selective pressures at work to inspire this adaptation. This has been most attributed to the independence of animals from liquid water as a means of fertilization among terrestrial species, however other differentiations at the microscale could have also contributed to the change between oogamy and internal fertilization. One explanation has been the cytoplasmic differences between two gametes, however Randerson & Hurst debunked this theory as unsupported (2001). Most alternative explanations that followed focused on selection based off size, behavioral interactions between gamete cells, and the allocation of resources ecologically. For the selection of gamete size necessary to catalyze the transition from isogamy to oogamy, the fitness of an organism would have to increase as egg size increases, and increase as sperm size decreases. The number of gametes within the organism alone would exist as a type ...
246 Clayton Road, Clayton, Victoria 3168, Australia. Introduction. In vitro fertilization techniques were initially adopted for the treatment of couples in which the female suffered from inoperable tubal blockage. Following the initial birth of Louise Brown in July 1978 (24), and the subsequent births that followed, it became evident that a wider range of infertility problems could be treated by in vitro fertilization (IVF). Today, the primary indications for treatment by IVF are absence of a functional fallopian tube, poor sperm quality and refractory anovulation. In all these indications the current technology available has increased the options and chances of success. New applications in the treatment of infertility. Patient treatment has improved as a result of both scientific and clinical research. Improvements have been made in all the stages of treatment, commencing from the initial stage of induction of ovulation to the final step of transfer. For the induction of ovulation the use of ...
As abortion opposition rallies, some activists are taking aim at in vitro fertilization, frozen embryos. CHICAGO - Rosaries in hand, a small group of abortion opponents gathered outside a medical facility to pray for the unborn.. It was a familiar ritual held at an unconventional location: a fertility clinic.. An annual Bike for Life fundraiser culminated on a recent Saturday at the Naperville Fertility Center, a site where technology and science are typically heralded for enabling life where it was once deemed impossible.. Yet the crowd out front expressed concern for the fate of frozen embryos inside - particularly those that might be discarded, cryo-preserved indefinitely or donated for research - as a result of in vitro fertilization, considered the most effective form of assisted reproductive technology.. When you do IVF, you create a life, but how many lives does it take? said John Zabinski, founder of the bicycling event, which is organized by a local council of the Knights of Columbus. ...
In Vitro Fertilization IVF Definition - In vitro fertilization (IVF) is the process of collecting a womans egg and a mans sperm and combining them in a....
Some Lupus Warriors treat infertility with in vitro fertilization (IVF). Although effective, in vitro fertilization can also cause serious symptom flares...
In Vitro Fertilization (IVF) In vitro fertilization (IVF) can make pregnancy possible for couples that want to carry a baby of their own but have been
IVF - In Vitro Fertilisation prices from ₹201592 - Enquire for a fast quote ★ Choose from 347 IVF - In Vitro Fertilisation Clinics in India with 145 verified patient reviews.
Sulfur-coated urea products can only be applied in granular form, and thus cannot be applied via liquid fertilization methods. ... These fertilizers mitigate some of the negative aspects of urea fertilization, such as fertilizer burn. The coatings release ... Labeling of fertilizer Turf management Urea-formaldehyde Christians, Nick (2004). "Fertilization". Fundamentals of Turfgrass ...
Fertilization is the fusion of gametes to produce a new organism. In animals, the process involves a sperm fusing with an ovum ... Depending on the animal species, the process can occur within the body of the female in internal fertilization, or outside in ... Slow block begins the first few seconds after fertilization and is when the release of calcium causes the cortical reaction, ... Chapter 7 Fertilization: Beginning a new organism. Retrieved 3 October 2020. Gilbert, Scott (2000). Developmental Biology. 6th ...
Integrated fish farming in China Chapter 3 POND FERTILIZATION AND FISH FEEDS. Pond Fertilization. Integrated Fish Farming in ... Chapter III Pond fertilization and fish feeds. Network of Agriculture centres in Asia, Bangkok, Thailand. 371 pp. Young, S.-S ...
Where Does Foliar Fertilization Fit In?, Plant Nutrition TODAY, International Plant Nutrition Institute (IPNI), Spring 2008, No ... Fageria, N. K.; Filho, M.P. Barbosa; Moreira, A.; Guimarães, C. M. (2009). "Foliar Fertilization of Crop Plants". Journal of ... George Kuepper, NCAT Agriculture Specialist (2003). "Foliar Fertilization". ATTRA Publication #CT135. ...
In-vitro fertilization is the process of combining an egg (oocyte) and sperm outside of the body with intent of fertilization. ... In vitro fertilization". The New England Journal of Medicine. 356 (4): 379-86. doi:10.1056/NEJMcp065743. PMID 17251534. Levy B ... Pre-implantation genetic diagnosis (PGD) is used in conjunction with in-vitro fertilization. ...
Cooper, Geoffrey M. (2000). "Meiosis and Fertilization". The Cell: A Molecular Approach. 2nd Edition. Brown, Terence A. (2002 ...
Fertilization is the fusion of two gametes. Copulation is the union of the sex organs of two sexually reproducing animals for ... Mating may also lead to external fertilization, as seen in amphibians, fishes and plants. For the majority of species, mating ... Fertilization' - definition of". Farlex, Inc. Retrieved 25 January 2014. Libbie Henrietta Hyman (15 September 1992). Hyman's ... Vertebrates (such as reptiles, some fish, and most birds) reproduce with internal fertilization through cloacal copulation (see ...
Fertilization occurs externally. The eggs become sticky after they are released into the water and will attach to the bottom ... A few days after the fertilization of zebra mussel eggs, a microscopic larva emerges called a veliger. During this initial ... in water just prior to adding it to the eggs and the combination is gently stirred for about a minute to achieve fertilization ...
"Cross-fertilization - Definition". Free Merriam-Webster Dictionary. Merriam-Webster, Incorporated. Retrieved 2011-03-10. " ...
Fertilization is internal. The female snail lays her eggs enclosed in a jelly-like matrix that she sometimes broods with her ...
Fertilization is external. Fertilized eggs hatch into free-swimming trochophore larvae. In some species, the larva briefly ...
Fertilization is internal. The male inserts one clasper into the female oviduct orifice and injects sperm along a groove on the ... Immediately following fertilization, the eggs are surrounded by thin shells called "candles" with one candle usually ...
Fertilization is random. Males generally reach sexual maturity at four years, whereas females reach maturity at five or six ...
Fertilization occurs externally; once the eggs are laid, the male covers them in his sperm. Between five and 10 offspring are ...
external fertilization A type of fertilization in which a sperm unites with an egg external to the body or bodies of the parent ... internal fertilization A type of fertilization which takes place inside the egg-producing individual. International System of ... zygote A eukaryotic cell formed by a fertilization event between two gametes. Contents: 0-9 A B C D E F G H I J K L M N O P Q R ... Contrast internal fertilization. extinction The termination of the existence of a particular kind of organism or a particular ...
CS1 maint: discouraged parameter (link) Keller, Sarah (1996). "IUDs Block Fertilization". Network. Family Health International ...
Fertilization occurs externally. The eggs are adhesive and stick to the rocky substrate. The young are swept downstream after ...
In Vitro Fertilization; Goose Bumps; Hummingbirds (October 30, 1993) Newspaper; Bomb Squad; Echoes; Mosquitoes (November 6, ...
Crichton, E. G. (2000). Sperm storage and fertilization. Reproductive biology of bats, 295-320. CONSTANTINE, D. G., 2003, ...
Some act before fertilization and others after it. Similar barriers exist in plants, with differences in flowering times, ... Some act before fertilization; others after it. In plants, some barriers to hybridisation include blooming period differences, ...
Loeb, Jacques (1913). Artificial parthenogenesis and fertilization. University of Chicago Press. jacques loeb sea urchin. Allen ... on this front Morgan showed that sea urchin eggs could be induced to divide without fertilization by adding magnesium chloride ... "On the Nature of the Process of Fertilization and the Artificial Production of Normal Larvae (Plutei) from the Unfertilized ...
Before fertilization, the sporangium and its contents plus its coat is called an 'ovule'; after fertilization a 'seed'. In ... self-fertilization). When a pollen grain reaches an ovule, it enters via a microscopic gap in the coat (the micropyle). The ... and fertilization of the ovum takes place within the archegonium rather than in the external environment. Secondly, and most ...
... this is in contrast with in vitro fertilisation (IVF). In plants, the fertilization process is referred to as pollination. It ... Assisted reproductive technology Conception device Fertilisation Internal fertilization Sperm bank Sperm donation Traumatic ... Only a small proportion of the sperm in each ejaculation reach the site of fertilization in the fallopian tubes, their numbers ... If ovulation occurs and the sperm encounter an ovum in the fallopian tube, fertilization may occur. A woman may also be ...
Full article: Iron Fertilization Iron fertilization is a facet of geoengineering, which purposefully manipulates the Earth's ... Ongoing investigations regarding artificial fertilization exist. Due to the scale of the ocean and the fast response times of ... Aumont, O.; Bopp, L. (2006-06-01). "Globalizing results from ocean in situ iron fertilization studies". Global Biogeochemical ... Chisholm, S; Falkowski, P; Cullen, J (2001). "Dis-crediting ocean fertilization". Science. 294 (5541): 309-310. doi:10.1126/ ...
Self-fertilization can occur. Parasites of Bulinus forskalii include: as intermediate host for Schistosoma guineensis as ...
IVF, or in vitro fertilisation, is when mature eggs are collected from ovaries and fertilized by sperm in a lab and then ... "In vitro fertilization (IVF)". Mayo Clinic. Mayo Clinic. Retrieved May 15, 2020. Griffiths, Anthony. "Aneuploidy". An ... Preimplantation refers to the state of existing or occurring between the fertilization of an ovum and its implementation in the ...
These fish have external fertilization. Mating is initiated when males pursue a female and nudge her abdomen. When the female ... generally with at least ten minutes between fertilizations. The speckled chub does not guard its eggs from potential predators ...
Moore, J. M.; Harris, G. H. "Fertilization" (PDF). Retrieved 26 July 2014. Proctor, Robert N. (2006-12-01). " ...
... an in vitro fertilization program; and special pharmaceutical services. A portion of land on the UMMC campus was once the site ... an in vitro fertilization program; and special pharmaceutical services. In 2007, professional football standout Eli Manning ...
Pollination by birds Mistletoes and birds Ingersoll E (1920). "Flowers, Fertilization of, by Birds" . Encyclopedia Americana.. ...
IVF: A Complete Guide to Understanding In Vitro Fertilization. In Vitro Fertilization(IVF) is the main type of assisted ... Because fertilization takes place outside the body (without the use of fallopian tubes), its an option for women whove had ... When you first set out to use in vitro fertilization, doctors are going to restart your hormone cycle so that they can more ... If the sperm is already highly motile, the sperm and eggs are combined in a dish, and hopefully fertilization takes place ...
Among vertebrates, external fertilization is most common in amphibians and fish. Invertebrates utilizing external fertilization ... External fertilization typically occurs in water or a moist area to facilitate the movement of sperm to the egg. The release of ... In some cases, fertilization can take place on a spawning animals surface and when the animals are in the turbulent wake. ... Although fertilization is usually thought of as a short-term process, there is the possibility of gametes being retained on the ...
Fertilization which takes place inside the female body is called internal fertilization in animals is done through the ... Internal fertilization, unlike its counterpart, external fertilization, brings more control to the female with reproduction. ... Fewer offspring are produced through internal fertilization in comparison to external fertilization. This is both because the ... external fertilization) and in others are retained by the "mother" (internal fertilization). At some point, the growing egg or ...
cross-fertilization (countable and uncountable, plural cross-fertilizations) *Fertilization by the union of gametes of ... fertilization by the union of gametes of different plants (sometimes of different species) ... Retrieved from "" ...
Fertilisation in protists[edit]. Fertilisation in protozoa[edit]. There are three types of fertilisation processes in protozoa: ... Fertilisation or fertilization (see spelling differences), also known as generative fertilisation, insemination, pollination,[1 ... This article is about fertilisation in animals and plants. For fertilisation in humans specifically, see Human fertilization. ... Fertilisation in plants[edit]. In the Bryophyte land plants, fertilisation takes place within the archegonium. This moss has ...
Krutzsch P.H., Crichton E.G. (1991) Fertilization in Bats. In: Dunbar B.S., ORand M.G. (eds) A Comparative Overview of ... Uchida, T. A., 1957, Fertilization and hibernation in bats, Heredity (Tokyo) 11: 14-17.Google Scholar ... Hiraiwa, Y. K., and Uchida, T. A., 1956b, Fertilization in the bat, Pipistrellus abramus. A successful example of artificial ... Hiraiwa, Y. K., and Uchida, T. A., 1956a, Fertilization in the bat, Pipistrellus abramus abramus (Temminck) III. Fertilizing ...
in vitro fertilization vē´trō, vĭ´trō [key] (IVF), technique for conception of a human embryo outside the mothers body. ... See also artificial insemination ; fertilization ; reproductive system ; surrogate mother . See L. Andrews, The Clone Age (1999 ... If fertilization is successful, a fertilized ovum (or several fertilized ova), after undergoing several cell divisions, is ... By 2012 the use of in vitro fertilization had resulted in the birth of more than 5 million babies worldwide. Nevertheless, the ...
In other words, fertilization is an event that occurs when a single sperm enters a mature egg, releasing its genetic material ... Fertilization is the union of male sperm and female egg. ... What Does Fertilization Mean?. * When Are You Fertile? *How ... Fertilization is the union of male sperm and female egg. In other words, fertilization is an event that occurs when a single ... home/health & living health center/what does fertilization mean center /what does fertilization mean? article ...
Fertilization-the fusion of gametes to produce a new organism-is the culmination of a multitude of intricately regulated ... In Caenorhabditis elegans, fertilization is highly efficient. Sperm become fertilization competent after undergoing a ... Fertilization Oocyte-to-embryo transition Egg activation Spermiogenesis Sperm activation Eggshell Polyspermy Sperm migration ... Marcello MR, Singson A (2010) Fertilization and the oocyte-to-embryo transition in C. elegans. BMB Rep 43(6):389-399PubMed ...
In vitro fertilization has resulted in an estimated 4000-5000 births in the world. The procedure has been accepted in Europe, ... Fertilization.html?id=bp1sAAAAMAAJ&utm_source=gb-gplus-shareClinical In Vitro Fertilization. ... In vitro fertilization has resulted in an estimated 4000-5000 births in the world. The procedure has been accepted in Europe, ... embryo transfer embryo viability embryos frozen Fert Embryo Transfer Fertil Steril fertilization and embryo fertilization rate ...
A fertilization rate of 2 or 3 mg nitrogen (N) per week for 20 weeks yielded longleaf pine (Pinus palustris) seedlings grown ... Container longleaf pine seedling morphology in response to varying rates of nitrogen fertilization in the nursery and ...
Assortative fertilization is a subtype of fertilization barrier that depends upon characters of the female and male such that ... A failure at any of these steps prevents fertilization. To promote assortative fertilization, there must be some degree of ... In organisms such as Drosophila where fertilization is internal and females store sperm, postmating barriers to fertilization ... Our interest, however, is not in all barriers to fertilization, only with those that underlie assortative fertilization. ...
While CO2 fertilization could help to increase above ground vegetation a bit, storing more than a few tens of percent of the ... This effect is known as "CO2 fertilization" because, in the envisioned scenario, higher ambient CO2 concentrations in the ... A few simple calculations indicate that any hypothesized co2 fertilization response is unlikely to offset a significant ... "co2 fertilization" could potentially provide a strong negative feedback on changing CO2 concentrations. ...
VA regulations were amended to offer in vitro fertilization (IVF) evaluation and treatment to Veterans with certain service- ... In Vitro Fertilization Treatment. Veterans with certain service-connected conditions that result in infertility may be eligible ... Handout for Veterans: In Vitro Fertilization Treatment. Describes availability of IVF treatment for Veterans and their spouses. ... Describes treatment options available for Veterans with service-connected infertility, including in vitro fertilization (IVF) ...
Insemination and fertilization. During these steps, the male partners sperm is mixed with the best of the retrieved eggs, to ... This happens about three or four days after fertilization occurs and requires a single cell to be removed from each embryo. ... Embryo transfer into the womb is carried out within three to five days after fertilization. It must implant into the ... It started in 1978 with the birth of Louise Brown by in vitro fertilization (IVF) to a previously infertile couple. ...
Synonyms, antonyms, and other words related to self-fertilization:. = 48 && event.charCode <= 57 value="Num letters..." ...
Mechanism and control of animal fertilization. Cell biology. Personality and Psychopathology. Cell Biology - Academic Press. ... cortical reaction cytoplasmic decondensation Dunbar egg surface embryo envelope enzyme Epel epididymal Fawcett fertilization ... gb-gplus-shareMechanism and control of animal fertilization. ... Mechanism and control of animal fertilization. John F. Hartmann ...
... and his theory of the adaptation of flowers to fertilisation by insects is one that will ever be associated with his name. In ... CHRISTIAN CONRAD SPRENGELS treatise on the structure and fertilisation of flowers, after well nigh a century of oblivion, has ... The Fertilisation of Flowers Nature volume 28, pages513-514(1883)Cite this article ... The Fertilisation of Flowers.. By Prof. Hermann Müller. Translated and Edited by DArcy W. Thompson, B.A., Scholar of Trinity ...
... Goto Sponge NotDistinct Permalink An Entity of Type : owl:Thing, within Data Space : ...
In vitro fertilization (IVF), medical procedure in which mature egg cells are removed from a woman, fertilized with male sperm ... In vitro fertilization (IVF), also called test-tube conception, medical procedure in which mature egg cells are removed from a ... Fertilization generally occurs within 12 to 48 hours. The potential embryo is then placed in a growth medium, where it is ... In vitro fertilization is generally undertaken only after an exhaustive evaluation of infertility has been made. A number of ...
And if you want a better understanding of the whys and how-tos of fall fertilization, weve created this easy-to-follow fall ... A lush, green and healthy spring lawn starts with fall fertilization. ... fertilization infographic just for you.. From when to fertilize to which lawn fertilizers to use and tips for choosing the ...
... ... The findings link exposure to PFRs in women undergoing IVF to a lower probability of embryo fertilization and implantation, as ... The women with the highest concentrations of PFR metabolites had lower rates of successful fertilization and implantation of ... in urine is associated with negative in vitro fertilization (IVF) outcomes in women, according to an NIEHS-funded study. ...
... such as iron fertilization, "may have unintended consequences." ... about the practice of iron fertilization, the researchers claim ...
Nitrogen Fertilization. INTRODUCTION Maintenance of a snow cover during the winter is necessary for successful winter wheat ... Consequently, N fertilization has an important influence on both the income and expense columns of the winter wheat balance ... Yield responses to N will be small if the plants early season demands are not met because of delays in N fertilization. A ... Late fall N fertilization avoids this problem. However, reduced grain yield and percent protein, attributed primarily to ...
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In vitro double fertilization[edit]. In vitro double fertilization is often used to study the molecular interactions as well as ... Double Fertilization in Gymnosperms[edit]. A far more rudimentary form of double fertilization occurs in the sexual ... Double fertilization is a complex fertilization mechanism of flowering plants (angiosperms). This process involves the joining ... Double fertilization was discovered more than a century ago by Sergei Nawaschin and Grignard in Kiev,[4] Russian Empire, and ...
The number of people who can be fed from the agricultural yield of one hectare has more than doubled from 1.9 to 4.3 over the past hundred years.
From a quarter to half of Earths vegetated lands has shown significant greening over the last 35 years largely due to rising levels of atmospheric carbon dioxide, according to a new study.
In many apomictic plants, seed development does occur without fertilization or with only partial fertilization (3). In ... Fertilization-independent seed development in Arabidopsis thaliana. Abdul M. Chaudhury, Luo Ming, Celia Miller, Stuart Craig, ... Fertilization-independent seed development in Arabidopsis thaliana. Abdul M. Chaudhury, Luo Ming, Celia Miller, Stuart Craig, ... Fertilization-independent seed development in Arabidopsis thaliana. Abdul M. Chaudhury, Luo Ming, Celia Miller, Stuart Craig, ...
Some embryos are destroyed as a result of in vitro fertilization. Does the ... ... Some embryos are destroyed as a result of in vitro fertilization. Does the federal government fund embryo destruction through ...
  • Fertilisation or fertilization (see spelling differences ), also known as generative fertilisation , insemination , pollination , [1] fecundation , syngamy and impregnation , [2] is the fusion of gametes to initiate the development of a new individual organism . (
  • Insemination and fertilization. (
  • In-vitro fertilization is ideal for women who have not been able to become pregnant through regular unprotected intercourse or after 12 cycles of artificial insemination. (
  • In a process called insemination , the sperm and eggs are mixed together and stored in a laboratory dish to encourage fertilization. (
  • The SGF Tampa practice was formed in 2018, and provides convenient access to highly specialized fertility care, including diagnostic testing and low and high tech treatment options, such as intrauterine insemination (IUI), in vitro fertilization (IVF), donor egg treatment, egg freezing, oncofertility and LGBTQ family building. (
  • She had received 3 cycles of clomiphene citrate and 2 cycles of ovulation induction (OI) and artificial insemination before the in vitro fertilization (IVF) attempts. (
  • It is contrasted with internal fertilization, in which sperm are introduced via insemination and then combine with an egg inside the body of a female organism. (
  • in vitro fertilization vē´trō, vĭ´trō [ key ] (IVF), technique for conception of a human embryo outside the mother's body. (
  • In vitro fertilization (IVF) , also called test-tube conception , medical procedure in which mature egg cells are removed from a woman, fertilized with male sperm outside the body, and inserted into the uterus of the same or another woman for normal gestation . (
  • The process of fertilization is also known as conception, fecundation and syngamy. (
  • However, when a couple has difficulty conceiving in the traditional manner, in vitro fertilization allows for conception outside the body. (
  • McMahon CA, Ungerer JA, Tennant CC and Saunders DM (2000) Psychosocial adjustment and the quality of the mother-child relationship at four months postpartum after conception by in vitro fertilization. (
  • In vitro fertilization can be used when other conception methods have proven unsuccessful. (
  • This is in contrast to normal 'in vivo' conception, in which fertilization occurs in the fallopian tube of a woman's reproductive tract. (
  • Archbishop Jozef Michalik, chairman of the Episcopate, said that it didn't matter for the Church which parties lent their support to the legislative proposal as long as they understood the Church's position on the need to protect all human life from the moment of conception and its condemnation of in vitro fertilization, where embryos are routinely destroyed. (
  • March 10, 2017 ( LiveActionNews ) -- The scientific community continues to prove that human life begins at conception (fertilization). (
  • The first cell of a new and unique human life begins existence at the moment of conception (fertilization) when one living sperm from the father joins with one living ovum from the mother. (
  • In other words, fertilization is an event that occurs when a single sperm enters a mature egg, releasing its genetic material into that egg. (
  • Fertilization generally occurs in a fallopian tube (uterine tubes). (
  • if the fertile cervical mucus is present, having intercourse before ovulation occurs can ensure sperm is waiting for the egg, giving the egg a higher chance of fertilization. (
  • The highly specialized gametes begin their interactions by signaling to one another to ensure that fertilization occurs when they meet. (
  • Involving either positive assortative fertilization (as opposed to self-incompatibility) or negative assortative fertilization, it occurs after mating but prior to fertilization. (
  • The difference is that assortative fertilization occurs at a later place in the sequence between mating and offspring production. (
  • These transparent eggs are valuable for studies observing living cells and for biochemical and molecular investigations because the time of fertilization can be accurately fixed, the development of many eggs occurs at about the same rate under suitable conditions, and large quantities of the eggs are obtainable. (
  • This happens about three or four days after fertilization occurs and requires a single cell to be removed from each embryo. (
  • Fertilization generally occurs within 12 to 48 hours. (
  • A far more rudimentary form of double fertilization occurs in the sexual reproduction of an order of gymnosperms commonly known as Gnetales. (
  • In many animals, such as mammals, fertilization occurs inside the body of the female. (
  • Fertilization occurs when a sperm penetrates the outer layer of the egg. (
  • Subchorionic hematoma occurs more frequently in in vitro fertilization pregnancy. (
  • In flowering plants, reproductive function is confined inside of the flower, where sex cells are produced, fertilization occurs and seeds eventually develop. (
  • These results indicate that what has been observed in in vitro fertilization (IVF) differs significantly from what occurs during "physiological" fertilization. (
  • External fertilization typically occurs in water or a moist area to facilitate the movement of sperm to the egg. (
  • Fertilization occurs naturally when upwellings bring nutrient-rich water to the surface, as occurs when ocean currents meet an ocean bank or a sea mount. (
  • Embryos are placed into the woman's womb 3 to 5 days after egg retrieval and fertilization. (
  • Some embryos are destroyed as a result of in vitro fertilization. (
  • A new study published in the journal Fertility and Sterility in February 2020 reports a higher risk for mortality in children who were conceived by the in vitro fertilization (IVF) technique followed by freezing of the embryos, compared to those naturally conceived, but only in the first few weeks of life. (
  • Once the embryos are ready for transferring, between two and five days after fertilization, your doctor will use a tube to gently release the embryos into your uterus. (
  • The ethical issues with in vitro fertilization include the many human embryos killed in the IVF process, and the "pregnancy reductions" (read: abortions) that often follow. (
  • The embryos are usually transferred into the woman's uterus three to five days following egg retrieval and fertilization. (
  • Liquid nitrogen can be used to freeze embryos created during in vitro fertilization. (
  • Some couples decide to freeze embryos that are generated but not transferred during in vitro fertilization. (
  • The process involves ovulation induction, egg retrieval, fertilization and implantation of embryos into the uterus. (
  • About 2 or 3 days after fertilization, the clinician chooses the healthy embryos that will be transferred into the woman's uterus. (
  • These embryos have been produced in the procedure called in vitro fertilization, which seems to enjoy ever wider acceptance by the American public. (
  • A faulty understanding of the ethical drawbacks of in vitro fertilization has already led to a naive acceptance of the destruction of human embryos that now threatens to pave the way for embryonic stem cell research. (
  • Changes have been made to artificial reproduction regulations to limit the number of embryos implanted during in vitro fertilization, the Health Promotion Administration (HPA) said. (
  • A 2011 national survey conducted by the agency showed that out of those who had undertaken in vitro fertilization (IVF) in the country, only 31.7 percent had restricted the number of embryos implanted to one or two, a percentage that paled in comparison with Europe's 75.6 percent. (
  • This story probes the ethical boundaries of Assisted Reproduction Technologies, such as IVF or in vitro fertilization, which creates surplus embryos, and Preimplantation Genetic Diagnosis, which screens embryos for disease or for traits, such as gender. (
  • The study, which included a survey of outcomes for 263,375 in vitro fertilization cycles, found elective single-embryo transfer leads to fewer adverse results in comparison to the transfer of multiple embryos with in vitro fertilization. (
  • Historically, the transfer of multiple embryos with in vitro fertilization has been the preferred method to maximize pregnancy rates, but that practice also can result in twins, triplets and other multiple gestations as well as complications from premature birth. (
  • When people undergoing in vitro fertilization have many embryos to choose from and want to select the one most likely to grow into a healthy baby instead of miscarrying, the current practice is to pinch a few cells from the developing embryo to test them. (
  • The DNA tests, known scientifically as preimplantation genetic testing for aneuploidy (PGT-A) or comprehensive chromosome screening (CCS), aim to establish whether embryos made via in-vitro fertilization have the normal number of chromosomes-23 pairs-or perhaps one missing or one too many. (
  • If fertilization is successful, a fertilized ovum (or several fertilized ova), after undergoing several cell divisions, is either transferred to the mother's or a surrogate mother's body for normal development in the uterus, or frozen for later implantation. (
  • Problems that affect ovulation or the ability of the ovum to enter the fallopian tube and move to the proper place for fertilization can cause infertility in women. (
  • mamabunny26 and @mydamonn: From what I have known of in vitro fertilization, both the sperm and ovum are fertilized in a test tube and it is implanted into your uterus but before all that, the doctor must first get an ovum from the woman. (
  • How is the ovum transported to the site of fertilization? (
  • Self-fertilisation isn't uncommon in the animal world. (
  • Nematode worms have made the switch from sex to self-fertilisation several times. (
  • A new study found that switching to self-fertilisation shaves time off lifespans in a population, and researchers have a few ideas as to why. (
  • Fertilization in advanced plants is preceded by pollination , during which pollen is transferred to, and establishes contact with, the female gamete or macrospore. (
  • The gametes that participate in fertilisation of plants are the pollen (male), and the egg (female) cell. (
  • [10] ROS levels have been shown via GFP to be at their highest during floral stages when the ovule is the most receptive to pollen tubes, and lowest during times of development and following fertilization. (
  • Mr. Wilson's "fertilisation" being simply the discharge of the pollen from the anther, which may or may not "pollinate" the stigma and "fertilise" the ovules. (
  • He also finds fault with those botanists who distinguish between "cross-fertilisation" and "selffertilisation"-the fertilisation of ovules by pollen from a different or from the same flower-without being able to define accurately the physiological difference between the two processes. (
  • Double fertilisation is the process in angiosperms (flowering plants) in which two sperm from each pollen tube fertilise two cells in a female gametophyte (sometimes called an embryo sac) that is inside an ovule. (
  • Roles of the oviduct in mammalian fertilization, REPRODUCTION 144(6):649 (Oct. 1, 2012) (emphasis added). (
  • Mammalian fertilization comprises sperm migration through the female reproductive tract, biochemical and morphological changes to sperm, and sperm-egg interaction in the oviduct. (
  • This Review focuses on the advantages of studying fertilization using gene-manipulated animals and highlights an emerging molecular mechanism of mammalian fertilization. (
  • This study therefore provides strong evidence implicating the ubiquitin-proteasome pathway in mammalian fertilization and zona penetration. (
  • The eggs of marine invertebrates, especially echinoderms , are classical objects for the study of fertilization. (
  • During these steps, the male partner's sperm is mixed with the 'best' of the retrieved eggs, to encourage fertilization under controlled conditions. (
  • Disadvantages of external fertilization include a reliance on water and the large amount of wasted sperm and eggs that never reach a corresponding gamete, even when the organisms releasing the eggs and sperm are in close proximity. (
  • External fertilization is used only by animals that breed in water, since the sperm require water to swim through to reach the eggs. (
  • Because of the uncertain fertilization of any particular egg, animals that use external fertilization typically produce very large numbers of sperm and eggs. (
  • In internal fertilization, a male of a species directly inserts sperm into a female, which then swim in the fluids surrounding the reproductive tract to reach the eggs. (
  • We are rapidly making strides in identifying the functional role in fertilization of remote chemical communication between sperm and eggs," Zimmer said. (
  • In vitro fertilization (IVF) is a procedure that involves collecting a woman's eggs from her ovaries and fertilizing them with sperm in a laboratory. (
  • They transport eggs and are necessary for fertilization. (
  • IVF is the process of fertilization by extracting eggs, retrieving a sperm sample, and then manually combining an egg and sperm in a laboratory dish. (
  • The eggs are monitored to confirm that fertilization and cell division are taking place. (
  • Eggs are fertilized outside the body, then implanted in the uterus during in vitro fertilization. (
  • Fertilizing the eggs, also known as embryo culture, consists of mixing the eggs with sperm on a Petri dish that contains a medium suitable for fertilization. (
  • Donor eggs are now used in 12 percent of all in vitro fertilization (I.V.F.) attempts, making it among the fastest-growing infertility treatments. (
  • The eggs are then mixed with sperm in order to allow fertilization. (
  • Benthic sessile animals that make up the majority of invertebrates using external fertilization rely on ambient water motion to bring the sperm and eggs together. (
  • Fertilization by the union of gametes of different plants (sometimes of different species ). (
  • Fertilization-the fusion of gametes to produce a new organism-is the culmination of a multitude of intricately regulated cellular processes. (
  • These events were attributed to "chains of reaction that bring about the actual union of gametes, or fertilization proper. (
  • This, however, is only half of the story because, as with assortative mating, nonrandom union of gametes may vary between homogamy or positive assortative fertilization, and heterogamy, negative assortative fertilization, with implications for population differentiation similar to those of positive and negative assortative mating. (
  • This presentation will concern itself with factors influencing assortative fertilization, once copulation has occurred, but prior to zygote formation, during the "chains of reactions that bring about the actual union of gametes. (
  • Assortative fertilization is a subtype of fertilization barrier that depends upon characters of the female and male such that gametes from like or unlike parents have a greater or lesser than random chance of uniting. (
  • In the genus Drosophila , there is an incredible amount of variation in gametes and other internal reproductive characters with the potential to influence assortative fertilization. (
  • In all organisms the essence of fertilization is, in fact, the fusion of the hereditary material of two different sex cells , or gametes , each of which carries half the number of chromosomes typical of the species . (
  • The first significant event in fertilization is the fusion of the membranes of the two gametes, resulting in the formation of a channel that allows the passage of material from one cell to the other. (
  • We used fucoid seaweeds to examine whether marine organisms in intertidal and subtidal habitats might achieve high levels of fertilization by restricting their release of gametes to calm intervals. (
  • The website stated "GIFT is similar to IVF, but the gametes (egg and sperm) are transferred to the fallopian tubes rather than the uterus, and fertilization takes place in the tubes rather than in the laboratory. (
  • Double fertilization is a defining feature of flowering plants and involves two nonmotile male gametes (sperm cells) and two female gametes (egg cell and central cell). (
  • W. J. Snell, Plant gametes do fertilization with a twist. (
  • Fertilization is the process by which male and female haploid gametes (sperm and egg) unite to produce a genetically distinct individual. (
  • Sessile adult staged animals commonly produce gametes at the same times, also known as a synchronized release of gametes, for external fertilization in the water column. (
  • Although fertilization is usually thought of as a short-term process, there is the possibility of gametes being retained on the surface of an animal for an extended period of time. (
  • Veterans with certain service-connected conditions that result in infertility may be eligible for in vitro fertilization (IVF), or another form of assisted reproductive technology (ART) and other infertility services. (
  • Describes treatment options available for Veterans with service-connected infertility, including in vitro fertilization (IVF) and the process for obtaining care. (
  • In vitro fertilization is generally undertaken only after an exhaustive evaluation of infertility has been made. (
  • And while infertility treatments, such as in vitro fertilization (IVF), offer hope for would-be parents, the procedure comes with a high price tag. (
  • First successfully performed in 1978, in vitro fertilization (IVF) is probably one of the best known ART methods and quite possibly the most common form of treatment people think of when they think of infertility treatment. (
  • While in-vitro fertilization (IVF) seems to be a viable solution to infertility for many, the consequences of IVF are often hidden. (
  • Following the initial birth of Louise Brown in July 1978 (24), and the subsequent births that followed, it became evident that a wider range of infertility problems could be treated by in vitro fertilization (IVF). (
  • While the range of applications of in vitro fertilization now cover a wide spectrum, this chapter will predominantly deal with two techniques, one that is utilized to treat severe male infertility and the other used to diagnose for genetic defects in the preimplantation embryo. (
  • We present a case of a 36-year-old woman with a history of PCOS, infertility, and several attempts of ovulation induction and in vitro fertilization, who was diagnosed with tubal pregnancy and a well differentiated endometrial carcinoma. (
  • A small study by investigators from Harvard University suggests that cryopreserved embryo transfer (CET) is a strong independent risk factor for placenta accreta in women undergoing in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI). (
  • ART covers a wide spectrum of treatments such as in vitro fertilization (IVF), Intracytoplasmic sperm injection (ICSI) and Intracytoplasmic morphologically-selected sperm injection (IMSI). (
  • In some cases where there is a lower probability of fertilization, intracytoplasmic sperm injection (ICSI) may be used. (
  • First, a soil test should be made to establish the basis for a regular fertilization program. (
  • Our experts develop strategies and measures for sustainable soil management and optimum fertilisation application. (
  • We develop systems for fertilisation, organic matter management, crop rotation, tillage, mechanisation and the control of pests and diseases in the soil. (
  • Our experts in fertilisation, soil biology, tillage systems, mechanisation, cropping systems and management systems cooperate with businesses, government authorities and scientists from other fields of study. (
  • The fertilization needs of avocado trees vary depending on the soil in which the tree is planted. (
  • Three are provided by air and water, the other 12 must be provided by the soil or by supplemental fertilization. (
  • Citrus can be successfully grown in Texas without using either soil or leaf analyses to direct the fertilization program. (
  • Nutrient concentrations in plant biomass, nutrient standing crops and measurements of N and P availability in the soil indicated that one year after fertilization, the N-fertilizer had mostly 'disappeared' from N-fertilized plots, whereas the availability of P remained markedly enhanced in P-fertilized plots. (
  • According to a recent study in Human Reproduction, women who produce a low number of oocytes during in vitro fertilization (IVF) seem to have an increased risk of miscarriage. (
  • Pregnancy after in vitro fertilization of human follicular oocytes collected from nonstimulated cycles, their culture in vitro and their transfer in a donor oocyte program. (
  • Apart from the beneficial effects of oviductal cell monolayer and its conditioned medium on in vitro fertilization and embryonic development (24-27), the accumulated maternal mRNAs in oocytes have a crucial role in the success of normal fertilization and early embryo development, allowing the first cleavages to occur, before the activation of embryonic genome (28). (
  • In vitro fertilization (IVF) is a form of assisted reproductive technology in which a woman's reproductive system is artificially stimulated to produce oocytes, which are extracted, fertilized in a laboratory, and then implanted in the uterus. (
  • IVF is a multistep process involving ovarian stimulation, ovulation induction, collection of oocytes, fertilization with sperm, and transfer of the fertilized oocytes to the uterus for implantation and maturation. (
  • The oocytes are removed from the follicles by aspiration and incubated with sperm to enable fertilization. (
  • The choice of treatment can also depend on if the couple has had previous failures to achieve fertilization in an IVF treatment cycle and other factors such as failure of sperm to bind to the zona pellucida of the oocytes. (
  • Neither proteasome inhibitors nor antibodies had any effects on sperm-ZP binding and acrosome exocytosis in zona-enclosed oocytes or on fertilization rates in zona-free oocytes, which were highly polyspermic. (
  • Retrieved on September 25, 2020 from (
  • The result of fertilization is a cell ( zygote ) capable of undergoing cell division to form a new individual. (
  • After the process of fertilization, the zygote travels down the Fallopian tube toward the uterus. (
  • Human development begins at fertilization when a sperm fuses with an oocyte to form a single cell, the zygote. (
  • Embryo transfer into the womb is carried out within three to five days after fertilization. (
  • Boivin J and Takefman J (1996) The impact of the in vitro fertilization‐embryo transfer (IVF‐ET) process on emotional, physical and relational variables. (
  • Expanding insurance coverage to cover a type of in vitro fertilization known as elective single-embryo transfer could lead to improved health outcomes and lower health care costs, according to a new study that included researchers from the University of Colorado School of Medicine. (
  • The writers said their findings suggest insurance results in lower out-of-pocket expenses, which makes elective single-embryo transfer more attractive for those seeking in vitro fertilization. (
  • Fertilization barriers may occur for a variety of reasons: sterility of the male or female, lack of oviposition sites, age of the male or female, interference from the ejaculate of another male, and genotypes of the male and female. (
  • during parthenogenesis , in which fertilization does not occur, activation of an egg may be accomplished through the intervention of physical and chemical agents. (
  • Obstetric complications occur more frequently in pregnancies after in vitro fertilization (IVF). (
  • When can fertilization occur? (
  • Sexual selection may not seem to occur during external fertilization, but there are ways it actually can. (
  • Fertilization can also occur when weather carries wind blown dust long distances over the ocean, or iron-rich minerals are carried into the ocean by glaciers, rivers and icebergs. (
  • In vitro fertilization ( IVF ) is a laboratory procedure in which egg cells are fertilized outside a woman's body and then transferred to her uterus . (
  • After fertilization, the egg is implanted into the woman's uterus. (
  • Examples of assortative fertilization in Drosophila are reviewed and compared with those of other organisms. (
  • The fusion of egg and sperm is an essential step of fertilisation in sexually reproducing organisms and the molecular mechanism behind this event has long been the object of intense research. (
  • This solution tests spent embryo culture media for chromosomal abnormalities during in vitro fertilization treatment. (
  • Double fertilization is a complex fertilization mechanism of flowering plants ( angiosperms ). (
  • Evidence of double fertilization in Gnetales , which are non-flowering seed plants, has been reported. (
  • Double fertilization was discovered more than a century ago by Sergei Nawaschin and Grignard in Kiev , [4] Russian Empire , and Léon Guignard in France . (
  • [5] Lilium martagon and Fritillaria tenella were used in the first observations of double fertilization, which were made using the classical light microscope . (
  • Due to the limitations of the light microscope, there were many unanswered questions regarding the process of double fertilization. (
  • [9] The more primitive process of double fertilization in gymnosperms results in two diploid nuclei enclosed in the same egg cell. (
  • Recent Examples on the Web These double fertilization events seem to explain at least some honeybee gynandromorphs, though male-female hybrids in other species can manifest in other ways. (
  • These example sentences are selected automatically from various online news sources to reflect current usage of the word 'double fertilization. (
  • What made you want to look up double fertilization ? (
  • This process, called double fertilization, is unique to flowering plants. (
  • Finally, through the process of double fertilization, seedlings have available the nutrition that they need to begin germination. (
  • What Is Double Fertilization in Angiosperms? (
  • In Vitro Fertilization(IVF) is the main type of assisted reproductive technology(ART). (
  • Gametic isolation, as a form of reproductive isolation, is equivalent to positive assortative fertilization. (
  • In vitro fertilization, or IVF, is the most common and effective type of assisted reproductive technology to help women become pregnant. (
  • Both fertilization events are necessary for reproductive success. (
  • In Vitro Fertilization is an assisted reproductive technology (ART) commonly referred to as IVF. (
  • By lifting barriers to insurance coverage, we will ensure safe and affordable access to in vitro fertilization and help New Yorkers have better control over their reproductive health and family planning. (
  • The system is designed to transport the ova to the site of fertilization.The female reproductive system is designed to carry out several functions. (
  • Therefore, sensitivity to environmental factors can lead to successful external fertilization, even for species living in turbulent habitats. (
  • In the Bryophyte land plants, fertilisation takes place within the archegonium . (
  • One year after N-fertilization vascular plant growth was still co-limited by N and P, but one year after P-fertilization, vascular plant growth was only limited by N. Bryophyte biomass responded weakly to fertilization. (
  • During double fertilisation in angiosperms the haploid male gamete combines with two haploid polar nuclei to form a triploid primary endosperm nucleus by the process of vegetative fertilisation. (
  • The elevated levels of the toxin, which is also responsible for amnesiac shellfish poisoning in humans, raises "serious concern" about the practice of iron fertilization, the researchers claim. (
  • Scott Doney, a senior scientist at Woods Hole Oceanographic Institution in Massachusetts, told Zeitvogel that any form of geo-engineering, such as iron fertilization, "may have unintended consequences. (
  • Can Controversial Ocean Iron Fertilization Save Salmon? (
  • There's not evidence that that region is iron-limited,' argues phytoplankton researcher Maite Maldonado of the University of British Columbia, who sailed on one of the first experimental iron fertilization cruise in the Southern Ocean in 1999. (
  • Originating as an ecosystem experiment to test Martin's iron hypothesis, iron fertilization experiments are now used as powerful tools to study the world's oceans. (
  • But intentional iron fertilization over great expanses of the ocean may have unintended consequences for the world's largest ecosystem. (
  • Iron fertilization is the intentional introduction of iron to iron-poor areas of the ocean surface to stimulate phytoplankton production. (
  • The most recent open ocean trials of ocean iron fertilization were in 2009 (January to March) in the South Atlantic by project Lohafex, and in July 2012 in the North Pacific off the coast of British Columbia, Canada, by the Haida Salmon Restoration Corporation (HSRC). (
  • There are two ways of performing artificial iron fertilization: ship based direct into the ocean and atmospheric deployment. (
  • Iron-rich dust rising into the atmosphere is a primary source of ocean iron fertilization. (
  • Over-fertilization of commercial pot or container-grown crops results in high concentrations of soluble salts in the potting medium. (
  • Evidence for assortative fertilization will be presented, including some recent observations from my own laboratory. (
  • In vitro fertilization (IVF) is the joining of a woman's egg and a man's sperm in a laboratory dish. (
  • In vitro fertilization works by bringing an egg and sperm together in a laboratory setting to achieve the goal of fertilization, according to WebMD. (
  • During in vitro fertilization, sperm and embryo are joined in a laboratory setting. (
  • This process of fertilization takes place in a laboratory of a certified fertility clinic. (
  • In vitro fertilization in combination with preimplantation genetic diagnosis (IVF‐PGD) is a technique that helps couples avoid transmitting a genetic disorder to their offspring. (
  • The discovery of Juno and Izumo1 opened up new possibilities to study the process of fertilisation at the molecular level. (
  • In response to recent progress in understanding the structural requirements of the 'glycocode', a workshop on Glycobiology of Fertilization was held at the International University of Venice, Italy, in September 1998 to discuss the current state of the art of carbohydrate-based interactions during fertilization under molecular and structural aspects. (
  • UCLA graduate student Jeffrey Riffell and UCLA biology professor Richard Zimmer report the first experimental test on the role of small-scale physics as it influences the interactions between sperm and egg, and the consequences for fertilization, at the annual conference of the Association for Chemoreception Sciences in Sarasota, Fla., April 10. (
  • In flowering plants a second fertilisation event involves another sperm cell and the central cell which is a second female gamete. (
  • The process of sexual reproduction for cod involves the act of spawning, resulting in the egg and sperm coming together for fertilization in open water. (
  • Researchers at Karolinska Institutet in Sweden have taken a step closer to understanding the mechanism that leads to the fusion of egg and sperm at fertilisation. (
  • Proteasomal interference prevents zona pellucida penetration and fertilization in mammals. (
  • Sperm become fertilization competent after undergoing a maturation process during which they become motile, and the plasma membrane protein composition is reorganized in preparation for interaction with the oocyte. (
  • The oocyte releases prostaglandin signals to help guide the sperm to the site of fertilization, and sperm secrete a protein called major sperm protein (MSP) to trigger oocyte maturation and ovulation. (
  • After fertilization, the oocyte must quickly transition from the relative quiescence of oogenesis to a phase of rapid development during the cleavage divisions of early embryogenesis. (
  • This chapter will review the nature and regulation of the various cellular processes of fertilization, including the development of fertilization competence, gamete signaling, sperm-oocyte fusion, the oocyte to embryo transition, and production of an eggshell to protect the developing embryo. (
  • After a long journey, the spermatozoa meet the oocyte in the specific site of the oviduct named ampulla, and fertilization takes place. (
  • Fertilization , union of a sperm nucleus , of paternal origin, with an egg nucleus, of maternal origin, to form the primary nucleus of an embryo . (
  • Following the initial fertilization event, the second sperm nucleus is diverted to fertilize an additional egg nucleus found in the egg cytoplasm. (
  • The procedure is most often done 3 to 5 days after fertilization. (
  • There is an optimum amount of fluid motion where fertilization is significantly enhanced," said Zimmer, whose research is federally funded by the National Science Foundation. (
  • Optimum fertilisation systems are required to ensure a minimum of water and air pollution and efficient use of scarce raw materials such as phosphate and potash. (
  • This effect is known as "CO 2 fertilization" because, in the envisioned scenario, higher ambient CO 2 concentrations in the atmosphere literally "fertilize" plant growth. (
  • Indeed, following the general recommendations for nitrogen fertilization, coupled with close observation of visual symptoms of nutrient deficiency (and the correction thereof), is adequate for average production. (
  • Mathematical and experimental simulations predict that external fertilization is unsuccessful in habitats characterized by high water motion. (
  • What Are Disadvantages of External Fertilization? (
  • External fertilization also has advantages over internal fertilization. (
  • While this is a more reliable method in terms of the likelihood that each egg gets fertilized, it is more complicated than external fertilization. (
  • External fertilization is a mode of reproduction in which a male organism's sperm fertilizes a female organism's egg outside of the female's body. (
  • Among vertebrates, external fertilization is most common in amphibians and fish. (
  • Benthic marine plants also use external fertilization to reproduce. (
  • Environmental factors and timing are key challenges to the success of external fertilization. (
  • To look into the effect of female choice on external fertilization, an in vitro sperm competition experiment was performed. (
  • First-trimester exposure to maternal estradiol may increase risk of thyroid dysfunction in offspring conceived via in vitro fertilization (IVF), according to a study in Fertility & Sterility. (
  • USF Health is transitioning its in vitro fertilization (IVF) services and affiliating with Shady Grove Fertility (SGF) , a premier fertility and IVF organization with locations throughout Florida, as well as Georgia, Maryland, New York, Pennsylvania, Virginia and Washington DC. (
  • In vitro fertilization is common option for couples facing fertility problems. (
  • First among the results we had Darwin's own work on Orchids and on plants with heterogynous forms of styles, and attracted by these there came a long line of other more or less able investigators, of whom Hildebrand, Delpino, Fritz Müller, and others may be mentioned-some devoting themselves more to the details of floral mechanisms, others to the proof of the advantages of cross-fertilisation. (
  • Scientists have created a mathematical model that can help explain why so many pregnancies and in vitro fertilization attempts fail. (
  • Norby is among several scientists participating in a panel discussion titled "CO2 Fertilization: Boon or Bust? (
  • But scientists from the University of Bath are questioning the necessity of an egg in the equation, after successfully producing a litter of mice by bypassing the fertilization process. (
  • Multiple ocean labs, scientists and businesses have explored fertilization. (
  • In vitro fertilization, or IVF, is a method of fertilizing a woman's egg with a man's sperm outside the woman's body. (
  • This form of fertilization produces the world's largest marine habitats. (
  • Because fertilization takes place outside the body (without the use of fallopian tubes), it's an option for women who've had surgery to remove them. (
  • For fertilization to take place, sperm must be present either a couple of days prior to or on the day of ovulation . (
  • Before in vitro fertilization can take place, what do doctors have to determine about the female and male? (
  • If fertilization does not take place. (
  • In some cases, fertilization can take place on a spawning animal's surface and when the animals are in the turbulent wake. (
  • This allows for a variation in locations and time differences of fertilization taking place by the same invertebrate. (
  • The publication outlines the importance of fertilization, rates and timing of application, label requirements in Iowa, and fertilizer products in the market. (
  • Moving plants from high fertilization, high watering, fast growing conditions to less rapid growing conditions without first leaching fertilizer that will not be needed by the plant in the new environment. (
  • The idea of cross-fertilisation can scarcely be said to have established itself until 1859, and was a most powerful impetus to research based upon Sprengel's observations. (
  • This work, for which Darwin felt grateful-this book containing "an enormous mass of original observations on the fertilisation of flowers and on the part which insects play in the work," we quote again Darwin-the author himself styles "Ein Beitrag zur Erkenntniss des Ursächlichen Zusammenhanges in der Organischen Natur," but the translation says nothing of this. (
  • Eugster A and Vingerhoets AJJM (1999) Psychological aspects of in vitro fertilization: a review. (
  • However, in plots that were only fertilized in 1999 the effects of individual nutrients differed between the two years: N-fertilization slightly increased the amount of biomass produced in the same year (1999), whereas P-fertilization did so in the following year (2000). (
  • Senator Brian Harradine: "How often has in‑vitro fertilization been undertaken on non‑human higher primates? (
  • Old Masset village on the Haida Gwaii Islands off the British Columbia coast did this by contracting George and others to initiate the largest such intentional ocean fertilization effort to date. (
  • This article is about fertilisation in animals and plants. (
  • Because plants in turn, in the process of photosynthesis, convert CO 2 into oxygen, it is thus sometimes argued that such "co2 fertilization" could potentially provide a strong negative feedback on changing CO 2 concentrations. (
  • Growing plants under moisture conditions too dry for the fertilization rates employed. (
  • Unlike animals, however, plants are unable to actively seek mates, relying instead on other methods to accomplish fertilization. (
  • In addition, P-fertilization enhanced the uptake of N by plants the following year. (
  • In-vitro fertilization (IVF) can help achieve pregnancy when other treatments have not worked. (
  • anon118372: You can qualify for in vitro fertilization, but if you had miscarriages before it may happen during your pregnancy, so for me, just do the normal process and when you get pregnant, avoid accidents and also avoid dangerous drugs and other risks such as alcohol and smoking. (
  • Researchers looked at 156 women whose first pregnancy was conceived using in vitro fertilization, or IVF . (
  • [3] The cycle of fertilisation and development of new individuals is called sexual reproduction . (
  • The evolution of fertilisation is related to the origin of meiosis , as both are part of sexual reproduction , originated in eukaryotes . (
  • Relevant to students, academics and practitioners across the globe, this original volume highlights contemporary issues associated with assisted reproduction and embryology and critically analyzes the law surrounding human reproduction in the light of case law and technological developments since the Human Fertilisation and Embryology Act (HFE Act) Act was passed in 1990. (