Oogonia: Euploid female germ cells of an early stage of OOGENESIS, derived from primordial germ cells during ovarian differentiation. Oogonia undergo MEIOSIS and give rise to haploid OOCYTESOvary: 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.Stage-Specific Embryonic Antigens: Cell-surface molecules that exhibit lineage-restricted patterns of expression during EMBRYONIC DEVELOPMENT. The antigens are useful markers in the identification of EMBRYONIC STEM CELLS.Germ Cells: The reproductive cells in multicellular organisms at various stages during GAMETOGENESIS.Oomycetes: Eukaryotes in the group STRAMENOPILES, formerly considered FUNGI, whose exact taxonomic level is unsettled. Many consider Oomycetes (Oomycota) a phylum in the kingdom Stramenopila, or alternatively, as Pseudofungi in the phylum Heterokonta of the kingdom Chromista. They are morphologically similar to fungi but have no close phylogenetic relationship to them. Oomycetes are found in both fresh and salt water as well as in terrestrial environments. (Alexopoulos et al., Introductory Mycology, 4th ed, pp683-4). They produce flagellated, actively motile spores (zoospores) that are pathogenic to many crop plants and FISHES.Oogenesis: The process of germ cell development in the female from the primordial germ cells through OOGONIA to the mature haploid ova (OVUM).Ovum: A mature haploid female germ cell extruded from the OVARY at OVULATION.Meiosis: 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.Oocytes: 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).Ovarian Follicle: 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.Testis: 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.Tylenchida: An order of nematodes consisting of many species which are plant parasites. Female worms lay eggs that hatch either in soil or in the host plant.Secernentea: A subclass of nematodes characterized by numerous caudal papillae and an excretory system possessing lateral canals.Tylenchoidea: A superfamily of nematodes whose members are free-living saprophytes or parasites of plants. Ova are sometimes found in human feces after ingestion of infected plants.Asparagus Plant: A plant genus in the family LILIACEAE (sometimes placed in Asparagaceae) that contains ECDYSTEROIDS and is an ingredient of Siotone. The shoots are used as a vegetable and the roots are used in FOLK MEDICINE.Oviducts: 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.Weapons: Devices or tools used in combat or fighting in order to kill or incapacitate.Neanderthals: Common name for an extinct species of the Homo genus. Fossils have been found in Europe and Asia. Genetic evidence suggests that limited interbreeding with modern HUMANS (Homo sapiens) took place.Fucus: A genus of BROWN ALGAE in the family Fucaceae. It is found in temperate, marine intertidal areas along rocky coasts and is a source of ALGINATES. Some species of Fucus are referred to as KELP.Phaeophyta: 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.Ovule: The element in plants that contains the female GAMETOPHYTES.Germ Cells, Plant: The reproductive cells of plants.Ferns: Seedless nonflowering plants of the class Filicinae. They reproduce by spores that appear as dots on the underside of feathery fronds. In earlier classifications the Pteridophyta included the club mosses, horsetails, ferns, and various fossil groups. In more recent classifications, pteridophytes and spermatophytes (seed-bearing plants) are classified in the Subkingdom Tracheobionta (also known as Tracheophyta).Encyclopedias as Topic: Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)Cell Aggregation: The phenomenon by which dissociated cells intermixed in vitro tend to group themselves with cells of their own type.Granulosa Cells: Supporting cells for the developing female gamete in the OVARY. They are derived from the coelomic epithelial cells of the gonadal ridge. Granulosa cells form a single layer around the OOCYTE in the primordial ovarian follicle and advance to form a multilayered cumulus oophorus surrounding the OVUM in the Graafian follicle. The major functions of granulosa cells include the production of steroids and LH receptors (RECEPTORS, LH).Cumulus Cells: The granulosa cells of the cumulus oophorus which surround the OVUM in the GRAAFIAN FOLLICLE. At OVULATION they are extruded with OVUM.Fishes: A group of cold-blooded, aquatic vertebrates having gills, fins, a cartilaginous or bony endoskeleton, and elongated bodies covered with scales.Gills: Paired respiratory organs of fishes and some amphibians that are analogous to lungs. They are richly supplied with blood vessels by which oxygen and carbon dioxide are exchanged directly with the environment.Water: A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Fish Diseases: Diseases of freshwater, marine, hatchery or aquarium fish. This term includes diseases of both teleosts (true fish) and elasmobranchs (sharks, rays and skates).Fish Oils: Oils high in unsaturated fats extracted from the bodies of fish or fish parts, especially the LIVER. Those from the liver are usually high in VITAMIN A. The oils are used as DIETARY SUPPLEMENTS. They are also used in soaps and detergents and as protective coatings.Carbon Dioxide: A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.Earth (Planet): Planet that is the third in order from the sun. It is one of the four inner or terrestrial planets of the SOLAR SYSTEM.Evolution, Planetary: Creation and development of bodies within solar systems, includes study of early planetary geology.Water Supply: Means or process of supplying water (as for a community) usually including reservoirs, tunnels, and pipelines and often the watershed from which the water is ultimately drawn. (Webster, 3d ed)Tooth: One of a set of bone-like structures in the mouth used for biting and chewing.Geological Phenomena: The inanimate matter of Earth, the structures and properties of this matter, and the processes that affect it.Atmosphere: The gaseous envelope surrounding a planet or similar body. (From Random House Unabridged Dictionary, 2d ed)Genitalia, Female: The female reproductive organs. The external organs include the VULVA; BARTHOLIN'S GLANDS; and CLITORIS. The internal organs include the VAGINA; UTERUS; OVARY; and FALLOPIAN TUBES.Corpus Luteum: The yellow body derived from the ruptured OVARIAN FOLLICLE after OVULATION. The process of corpus luteum formation, LUTEINIZATION, is regulated by LUTEINIZING HORMONE.Physiology: The biological science concerned with the life-supporting properties, functions, and processes of living organisms or their parts.Uterus: 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.Chorionic Gonadotropin: 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).BooksAbortion, Induced: Intentional removal of a fetus from the uterus by any of a number of techniques. (POPLINE, 1978)Abortion, Spontaneous: Expulsion of the product of FERTILIZATION before completing the term of GESTATION and without deliberate interference.EssaysAbortion, Veterinary: Premature expulsion of the FETUS in animals.Periapical Tissue: Tissue surrounding the apex of a tooth, including the apical portion of the periodontal membrane and alveolar bone.Educational Measurement: The assessing of academic or educational achievement. It includes all aspects of testing and test construction.Abortion, Criminal: Illegal termination of pregnancy.
Oogonia Generally contain a single oospore. Antheridia Contain an elongated and club-shaped antheridium. Pythium-induced root ... are generally more host-specific. For this reason, Pythium spp. are more devastating in the root rot they cause in crops, ...
They are generally brown or dark green in color and consist of a holdfast, a stipe, and a frond. Oogonia and antheridia occur ... Numerous species are distributed throughout the temperate and tropical oceans of the world, where they generally inhabit ...
The creation of oogonia traditionally doesn't belong to oogenesis proper, but, instead, to the common process of gametogenesis ... In the brown alga Fucus, all four egg cells survive oogenesis, which is an exception to the rule that generally only one ... Oogonium -(Oocytogenesis)-> Primary Oocyte -(Meiosis I)-> First Polar Body (Discarded afterward) + Secondary oocyte -(Meiosis ... Oogenesis starts with the process of developing oogonia, which occurs via the transformation of primordial follicles into ...
In the conceptacles oögonia and antheridia are produced after meiosis and then released. Fertilisation follows and the zygote ... It grows to about 30 cm long and branches somewhat irregularly dichotomous and is attached, generally to rock, by a discoid ...
Generally, older leaves are resistant to infection, while younger leaves are more susceptible. P. manshurica can cause systemic ... Like other oomycetes, this is accomplished by the fertilization of oogonia by antheridia. This oospore will function as a ...
After migration primordial germ cells will become oogonia in the forming gonad (ovary). The oogonia proliferate extensively by ... 20 μm large somatic cell generally needs 24 hours to double its mass for mitosis. By this way it would take a very long time ... In human females there is proliferation of the oogonia in the fetus, meiosis starts then before birth and stands by at meiotic ... But then many of these oogonia die and about 50,000 remain. These cells differentiate into primary oocytes. In week 11-12 post ...
For oncology generally a large number of interphase cells are scored in order to rule out low-level residual disease, generally ... Hans von Winiwarter reported 47 chromosomes in spermatogonia and 48 in oogonia, concluding an XX/XO sex determination mechanism ... The cells are generally fixed repeatedly to remove any debris or remaining red blood cells. The cell suspension is then dropped ... It took until 1956 until it became generally accepted that the karyotype of man included only 46 chromosomes. The great apes ...
For instance, the cell walls of oomycetes are composed of cellulose rather than chitin and generally do not have septations. ... "Oomycota" means "egg fungi", referring to the large round oogonia, structures containing the female gametes, that are ... The Lagenidiales are the most primitive; some are filamentous, others unicellular; they are generally parasitic. However more ...
It is generally accepted that the resulting zygote forms a resting spore, which functions as a means of surviving adverse ... Briefly, the monoblephs form oogonia, which give rise to eggs, and antheridia, which give rise to male gametes. Once fertilized ...
It is termed an oogonium. The male organ is also large, bright yellow or red in colour, spherical in shape, and is usually ... It is probably this power of vegetative propagation which explains the fact that species of Characeae are generally found ... In others the monoecious condition is complicated by the development of the antheridium before the formation of the oogonium, ... The reproductive organs consist of antheridia and oogonia, though the structures of these organs differ considerably from the ...
Symptoms are generally similar among infected legumes, however timing and pattern of disease can differ among hosts and between ... A. euteiches exhibits no macroscopic signs, but oogonia and oospores can be seen in root tissue with a compound microscope. ... Symptoms of the disease can differ among hosts but generally include reduced root volume and function, leading to stunting and ... The antheridium fertilizes an oogonium, which then develops into a single oospore, which is 20-35 micrometers in diameter. When ...
The Oogonia multiply by dividing mitotically; this proliferation ends when the oogonia enter meiosis. The amount of time that ... Animal studies have generally showed correct imprinted DNA methylation establishment in oocytes resulting from follicle culture ... Development proceeds and the gametogonia turn into oogonia, which become fully surrounded by a layer of cells (pre-granulosa ... After beginning the meiotic process, the oogonia (now called primary oocytes) can no longer replicate. Therefore, the total ...
... is generally farmed using the floating raft method in which young laminaria sporophytes are attached to submerged ... The female egg matures in the oogonium until the male sperm fertilizes it. Life-Cycle: The most apparent form of Laminaria is ...
All of the oogonia and many primary oocytes die before birth. After puberty in primates, small groups of oocytes and follicles ... The term gonocyte is generally used to describe all stages post PGC until the gonocytes differentiate into spermatogonia. ... Mitotic germ stem cells, oogonia, divide by mitosis to produce primary oocytes committed to meiosis. Unlike sperm production, ...
Their retinas generally have both rod cells and cone cells (for scotopic and photopic vision), and most species have colour ... Oogonia development in teleosts fish varies according to the group, and the determination of oogenesis dynamics allows the ... The eggs have an average diameter of 1 millimetre (0.039 in). The eggs are generally surrounded by the extraembryonic membranes ... the blood and other tissue of sharks and Chondrichthyes is generally isotonic to their marine environments because of the high ...
Prokaryote species generally have one copy of each major chromosome, but most cells can easily survive with multiple copies. ... Hans von Winiwarter reported 47 chromosomes in spermatogonia and 48 in oogonia, concluding an XX/XO sex determination mechanism ... generally supercoiled. The DNA must first be released into its relaxed state for access for transcription, regulation, and ...
Root resistance is inherited and is generally expressed in the roots. In this case, the stem of a germinating seedling is most ... Oospores are made after the male gamete, antheridium, and female gamete, oogonium, undergo fertilization and then sexual ...
Oogonia development in teleosts fish varies according to the group, and the determination of oogenesis dynamics allows the ... The eggs have an average diameter of 1 millimetre (0.039 in). The eggs are generally surrounded by the extraembryonic membranes ...
Host resistance is also a method of controlling the pathogen, resistant plants generally have thicker cuticles which inhibits ... from other oomycetes by the presence of oval shaped papillate sporangia with short pedicles and spherical oogonia with narrow ...
M. maorum will generally reach a weight of up to 12 kg when fully grown. They live solitarily in a den for up to 3 months at a ... assigned 5 maturity stages for the egg development of Macroctopus maorum: Newly formed primary oogonia which has a small, ... a robust conical copulatory organ and arms of varying length with long unequal dorsal arms generally four to six times longer ...
Their retinas generally have both rods and cones (for scotopic and photopic vision), and most species have colour vision. Some ... Oogonia development in teleosts fish varies according to the group, and the determination of oogenesis dynamics allows the ... the red-bellied piranha is actually a generally timid scavenger species that is unlikely to harm humans. In the Book of Jonah a ...
Unlike a root system, the holdfast generally does not serve as the primary organ for water uptake, nor does it take in ... Fertilization may take place in the water with eggs and motile sperm, or within the oogonium itself. Certain species of brown ... The occurrence of Phaeophyceae as fossils is rare due to their generally soft-bodied nature, and scientists continue to debate ... The female gametophyte produces an egg in the oogonium, and the male gametophyte releases motile sperm that fertilize the egg. ...
Fry generally stay near where they were spawned for about a year before moving on. Albacore form schools based on their stage ... The creation of ova, known as oogenesis, begins with the rapid production of oogonia (undifferentiated germ cells that give ...
... does not occur in archaea or bacteria, which generally reproduce via asexual processes such as binary fission. However ... It is retinoic acid, derived from the primitive kidney (mesonephros) that stimulates meiosis in ovarian oogonia. Tissues of the ...
A typical teleost fish has a streamlined body for rapid swimming, and locomotion is generally provided by a lateral undulation ... such as oogonia). Since endocrine disruption also affects humans, teleosts are used to indicate the presence of such chemicals ...
... are why males generally do not grow prominent or well-developed breasts relative to females.[41][48] ...
Oogonia Generally contain a single oospore. Antheridia Contain an elongated and club-shaped antheridium. Pythium-induced root ... are generally more host-specific. For this reason, Pythium spp. are more devastating in the root rot they cause in crops, ...
They are generally brown or dark green in color and consist of a holdfast, a stipe, and a frond. Oogonia and antheridia occur ... Numerous species are distributed throughout the temperate and tropical oceans of the world, where they generally inhabit ...
However, the main oomycete pathogens of live fish (e.g., A. invadans and S. parasitica), do not generally (in case of A. ... When sexual reproduction occurs, the two dissimilar gametangial structures called the oogonium and the antheridium grow closer ... Some egg infecting species do produce oogonia (e.g., S. australis, S. diclina, S. ferax) but even in these species oospore ... together until they fuse, and haploid nuclei from the antheridia fertilize the eggs within the oogonia forming diploid oospores ...
Oogonia observed in posterior branch. Tail generally pointed, but may exhibit much variation. Males: Not found. ... Lip region continuous with body contour, generally bearing three annules, but occasionally three on one side and four on the ... Tail tapering, with 16-25 annules in a Senegal population (25-27 according to Seinhorst, 1968): terminus variable, generally ...
Creation of oogonia. The creation of oogonia traditionally doesnt belong to oogenesis, but to the common path of gametogenesis ... In the brown alga Fucus, all four egg cells survive oogenesis, which is an exception to the rule that generally only one ... Oogonium diploid/46 2N Oocytogenesis (mitosis) third trimester (forming oocytes) primary Oocyte diploid/46 4N Ootidogenesis ( ... Spermatogenesis (spermatogonium, spermatocyte, spermatid, sperm) - Oogenesis (oogonium, oocyte, ootid, ovum) - Germ cell ( ...
It is generally accepted that in females, oocyte production ceases during fetal development, with a finite number of oocytes ... 16 Although recent animal studies have suggested that primordial germ cells in vitro are capable of forming oogonia and ... The costs of ovarian-tissue preservation can be separated into 3 parts: (1) the procedure to retrieve the tissue, generally ...
In addition, they had the correct Oct4 expression, which is in contrast to most clones, and yet the latter are generally ... Here we show that mouse embryonic stem cells in culture can develop into oogonia that enter meiosis, recruit adjacent cells to ... Cultured embryonic stem cells are generally considered pluripotent rather than totipotent because of the failure to detect ...
Oogonium. Fertilization tube. antheridium 14. Order Leptomitales*Mostly aquatic, saprotrophic *Filamentous thallus with regular ... Filamentous species generally produce coenocytic hyphae *Principle storage compounds are water-soluble mycolaminarins (beta- ... Oogonia, antheridia and zoosporangia formed terminally *Branches and reproductive organs constricted at base and plugged with ... Oogonium grows through antheridium 13. Hypogynous. Paragynous/monoclinous. Paragynous/diclinous. Amphigynous. Oosphere. ...
11B-D). In the central and largest part of the gonad, the ovarian cavity was generally still separated in two parts by a ... GC, germ cell; I, intestine; K, kidney; M, mesentery; Oc, oocyte (primary); OC, ovarian cavity; Og, oogonia. ... The remaining 32% of the embryos had abnormal gonads in which the anterior end of the gonad generally appeared as a presumptive ... the gonads were female gonads that had grown in size and had differentiated into single hollow ovaries containing both oogonia ...
They generally begin to germinate in significant numbers shortly after bud break of grape, and populations of oospores may ... Sexual reproduction occurs through the fusion of antheridia and oogonia within the host tissue. Plasmopara viticola has only ...
... electroconvulsive remedial programme is then suggested At hand generally 20 weeks of gestation, the oogo- nia clusters break ... this case presumes that students force learn the material covered and this is unfortunately not generally speaking the if it ...
oogonium after mitosis oogonium are. called primary oocyte after the first. meiosis and arrest in the meiosis. diplotene stage ... Women in life generally only 400-500. follicles mature Roughly through. the following four processes Development and ... Embryo 6-8 weeks 600 thousand oogonia. Embryo 11-12 weeks First meiotic division Primary oocyte. Embryo 16-20 weeks 6-7 million ... hair, and the pubic hair generally has a characteristic flattop. pattern. All of them are due to E.. ESTROGENS ...
It has been generally accepted, as mentioned above, that mammalian ovary loses mitotic oogonia after birth. On the other hand, ... mitotic germ cells are histologically observed as oogonia and thus the proliferation of oogonia can supply mature eggs ... Mitotic germ cells, a good indication of oogonia, are no longer observed in ovary of many mammals after birth [2, 3]. ... Alternatively, certain differentiated oogonia also could provide a large pool of follicles through mitosis. But the cellular ...
In general, SCNT efficiencies have improved only marginally over the past decade, with the generally accepted rate of 5-15% of ... form either oogonia or spermatogonia. DNA methylation patterns are established such that sperm are hypermethylated and oocytes ... only a limited number of identical individuals are generally produced, and these clones are primarily used as breed stock. In ... Although these imprints are generally described by their DNA methylation patterns, the complex mechanisms and levels of ...
The Oogonia multiply by dividing mitotically; this proliferation ends when the oogonia enter meiosis. The amount of time that ... Animal studies have generally showed correct imprinted DNA methylation establishment in oocytes resulting from follicle culture ... Development proceeds and the gametogonia turn into oogonia, which become fully surrounded by a layer of cells (pre-granulosa ... After beginning the meiotic process, the oogonia (now called primary oocytes) can no longer replicate. Therefore, the total ...
It is clear, however, that both follicle cells and the ovum come from original oogonia. All ova develop from oogonia which ... Generally the eggs are not retained within the uterus for more than a day or so. There may be quite a few hours between the ... There has been no way to determine which oogonium is to be selected for maturation into an ovum and which will give rise to the ... They generally have a darkly staining nucleus, and the cytoplasm may be tapered toward one side. The spermatid, following ...
The nearshore region, although not precisely defined, is generally within kilometers of the coastline. 1 m = 3.3 ft. ... a) Dichotomosiphon, filament with oogonia and antheridia. (b) Ostreobium, filaments. (c) Caulerpa, section of filament showing ...
This is a hyphal mat with oogonia. Observe the large conspicuous oogonia within the mycelium. Inside the oogonia you can see ... In terrestrial habitats, they are generally parasitic. Important diseases caused by water molds are downy mildews (Peronospora ... Are there any oospores within the Oogonia? Can you see any antheridial hyphae attached to the oogonia? If you do, show other ... Examine the prepared slide of the Albugo sexual organs (oogonia and antheridia). The oogonia are evident as dense, red-staining ...
This is a hyphal mat with oogonia. Observe the large conspicuous oogonia within the mycelium. Inside the oogonia you can see ... Alchemy, generally, derives from the old French alkemie; and the Arabic al-kimia: "the art of transformation." The Arabs ... Are there any oospores within the Oogonia? Can you see any antheridial hyphae attached to the oogonia? If you do, show other ... Examine the prepared slide of the Albugo sexual organs (oogonia and antheridia). The oogonia are evident as dense, red-staining ...
Generally, if oogonia oocyte or mitosis meiosis development can be affected, oocytes can end up being abnormal or deceased even ... Notably, generally in most LSD1 substrates, just H3K4me2 levels had been changed considerably. The amount of H3K4me2 in ... actions of LSD1 on avoiding premature oocyte loss of life offers temporal specificity and whether its correlated with oogonia ...
Their retinas generally have both rod cells and cone cells (for scotopic and photopic vision), and most species have colour ... Oogonia development in teleosts fish varies according to the group, and the determination of oogenesis dynamics allows the ... The eggs have an average diameter of 1 millimetre (0.039 in). The eggs are generally surrounded by the extraembryonic membranes ... the blood and other tissue of sharks and Chondrichthyes is generally isotonic to their marine environments because of the high ...
Finally, a c-kit homolog is expressed in gonadal oogonia and growing oocytes as in mice but is also not found in PGCs. ... Interrater reliabilities were moderate to high, with those for CBT generally higher than those for IT. Association between the ...
It is proposed that DNA of interphase fetal oogonia is vulnerable to oxidative insults perpetrated by a nutritional stress to ... fetal oogonia; this condition was associated with up-regulation of the tumor suppressor/cell-cycle arrest modulator p53, ... In most mammals oogonia proliferate by mitosis and begin meiotic development during fetal life. Previous studies indicated that ... mammalian females are generally born with their full complement of (meiotic) gametes [30]. The normal chronology of ovarian ...
Different stages of oocytes (I~IV) and oogonia (og) are seen. The hybridization signal is strong in oogonia (inset) and stage-I ... It is generally accepted that a sexually bipotential germ cell pool makes the decision absolutely depending upon the gonadal ... In teleosts such as zebrafish [42], oogenesis proceeds from oogonia to oocytes of different stages. Distinction between oogonia ... and III oogonia (og3), respectively (FIG. S2A). Distinction of three types of oogonia became more evident at higher ...
Prokaryote species generally have one copy of each major chromosome, but most cells can easily survive with multiple copies.[33 ... Hans von Winiwarter reported 47 chromosomes in spermatogonia and 48 in oogonia, concluding an XX/XO sex determination mechanism ... It took until the mid 1950s until it became generally accepted that the karyotype of man included only 46 chromosomes.[38][39] ... Prokaryotic chromosomes and plasmids are, like eukaryotic DNA, generally supercoiled. The DNA must first be released into its ...
  • In Drosophila , it has been found that one oogonia can form a 16-cell-cyst through mitotic divisions, whereas, only one of these cells survives to form an oocyte, and the other cells inside the cyst die and provide necessary nutrients to the surviving oocyte [ 19 ]. (aging-us.com)
  • It is generally accepted that in females, oocyte production ceases during fetal development, with a finite number of oocytes present at birth. (aappublications.org)
  • It is proposed that DNA of interphase fetal oogonia is vulnerable to oxidative insults perpetrated by a nutritional stress to the dam, and that multiple/integrated adaptive molecular response mechanisms of cell-cycle inhibition (providing the time required for base repairs) and survival hence sustain the genomic integrity and population stability of the germline. (biomedcentral.com)
  • We hypothesized that fetal oogonia distressed as a result of nutrient deprivation express the tumor suppressor protein p53. (biomedcentral.com)
  • Vegetative growth and fertility of kelp gametophytes are thought to be antagonistic, such that most successful kelp recruitment is assumed to result from fertilization of single oogonia released from unicellular female gametophytes. (calstate.edu)
  • We used laboratory culture experiments to study the effect of temperature and nutrient addition on the per capita production of oogonia and sporophytes from Macrocystis pyrifera female gametophytes. (calstate.edu)
  • Furthermore, the production of multiple oogonia per female often led to the production of multiple sporophytes per female. (calstate.edu)
  • For example, two of the seedling pathogens ( Pythium and Phoma ) can cause root rots later in the season (21,23,33,43), but will not be discussed further as their impact is generally minor in comparison with the other more common root-rotting pathogens. (plantmanagementnetwork.org)
  • Cultured embryonic stem cells are generally considered pluripotent rather than totipotent because of the failure to detect germline cells under differentiating conditions. (sciencemag.org)
  • Development proceeds and the gametogonia turn into oogonia, which become fully surrounded by a layer of cells (pre-granulosa cells). (wikipedia.org)
  • In the 16th week, the sex cords begin to lose their coherence and form cell clusters, which surround the individual oogonia as flat follicular epithelium cells. (lecturio.com)
  • The mature male frog is generally smaller than the female, ranging from 60 to 110 mm. in length from snout to anus. (edu.au)
  • e.g. fish) show a very low overall incidence of atresia, and most of the oogonia produced during the lifespan of the female are ovulated as mature oocytes. (psu.edu)
  • 11. The female sex organ is single-celled oogonium. (yourarticlelibrary.com)
  • Each female gametophyte cell able to develop into a one-celled oogonium producing a single egg with remnants of flagellum (Motomura & Sakai 1988) which is extruded from oogonium, but remains attached to it. (algaebase.org)
  • Adult members are highly specialized, dioecious (having distinct male and female colonies, as opposed to hermaphroditic) parasites of the intestinal tract of a variety of vertebrates (but not generally humans). (encyclopediaofarkansas.net)
  • Our results indicate that individual multicellular female gametophytes can give rise to more than one oogonium and that per capita oogonia production significantly increases with the enhancement of culture conditions (i.e., decreased temperature and increased nutrient concentration). (calstate.edu)
  • Sheltered bedrock and boulders in the sublittoral fringe may be characterized by a mixed canopy of the kelps Laminaria digitata (usually in its broad-fronded cape form) and Saccharina latissima (both species generally frequent or greater). (marlin.ac.uk)
  • The relative abundance of fruticose forms and the sphericity and branch density of individual thalli are generally higher in wave beds than in current beds. (calstate.edu)
  • Chemical reactions may be facilitated by a catalyst, which is generally another chemical substance present within the reaction media but unconsumed (such as sulfuric acid catalyzing the electrolysis of water) or a non-material phenomenon (such as electromagnetic radiation in photochemical reactions). (blogspot.com)