Oviparity: The capability of producing eggs (OVA) from which young are hatched outside the body. While mostly referring to nonmammalian species, this does include MAMMALS of the order MONOTREMATA.Reptiles: Cold-blooded, air-breathing VERTEBRATES belonging to the class Reptilia, usually covered with external scales or bony plates.Viviparity, Nonmammalian: The capability of bearing live young (rather than eggs) in nonmammalian species. Some species of REPTILES and FISHES exhibit this.Amphibians: VERTEBRATES belonging to the class amphibia such as frogs, toads, newts and salamanders that live in a semiaquatic environment.Eggs: Animal reproductive bodies, or the contents thereof, used as food. The concept is differentiated from OVUM, the anatomic or physiologic entity.Ovum: A mature haploid female germ cell extruded from the OVARY at OVULATION.Birds: Warm-blooded VERTEBRATES possessing FEATHERS and belonging to the class Aves.Tribolium: A genus of small beetles of the family Tenebrionidae; T. confusum is the "confused flour beetle".Chitin Synthase: An enzyme that converts UDP glucosamine into chitin and UDP. EC 2.4.1.16.Beetles: INSECTS of the order Coleoptera, containing over 350,000 species in 150 families. They possess hard bodies and their mouthparts are adapted for chewing.Chitin: A linear polysaccharide of beta-1->4 linked units of ACETYLGLUCOSAMINE. It is the second most abundant biopolymer on earth, found especially in INSECTS and FUNGI. When deacetylated it is called CHITOSAN.Saprolegnia: A genus of OOMYCETES in the family Saprolegniaceae. It is a parasite and pathogen of freshwater FISHES.Insect Proteins: Proteins found in any species of insect.Sharks: A group of elongate elasmobranchs. Sharks are mostly marine fish, with certain species large and voracious.Reproduction: The total process by which organisms produce offspring. (Stedman, 25th ed)Fishes: A group of cold-blooded, aquatic vertebrates having gills, fins, a cartilaginous or bony endoskeleton, and elongated bodies covered with scales.Biological Evolution: The process of cumulative change over successive generations through which organisms acquire their distinguishing morphological and physiological characteristics.Sexual Behavior, Animal: Sexual activities of animals.Reproduction, Asexual: Reproduction without fusion of two types of cells, mostly found in ALGAE; FUNGI; and PLANTS. Asexual reproduction occurs in several ways, such as budding, fission, or splitting from "parent" cells. Only few groups of ANIMALS reproduce asexually or unisexually (PARTHENOGENESIS).Squalus acanthias: A species of shark in the family SQUALIDAE, used for its oil (SQUALENE) and as fish meal. It also figures heavily in biological research, especially with reference to its RECTAL GLAND in studies of WATER-ELECTROLYTE BALANCE.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)Australia: The smallest continent and an independent country, comprising six states and two territories. Its capital is Canberra.Victoria: A state in southeastern Australia, the southernmost state. Its capital is Melbourne. It was discovered in 1770 by Captain Cook and first settled by immigrants from Tasmania. In 1851 it was separated from New South Wales as a separate colony. Self-government was introduced in 1851; it became a state in 1901. It was named for Queen Victoria in 1851. (From Webster's New Geographical Dictionary, 1988, p1295 & Room, Brewer's Dictionary of Names, p574)Seafood: Marine fish and shellfish used as food or suitable for food. (Webster, 3d ed) SHELLFISH and FISH PRODUCTS are more specific types of SEAFOOD.Dictionaries, MedicalDictionaries as Topic: Lists of words, usually in alphabetical order, giving information about form, pronunciation, etymology, grammar, and meaning.Dictionaries, ChemicalTerminology as Topic: The terms, expressions, designations, or symbols used in a particular science, discipline, or specialized subject area.Ovoviviparity: The capability of producing yolk-filled eggs that hatch within the body, so that the young are born alive, but without placental attachment. This applies to certain species of REPTILES and FISHES.Animal Fins: Membranous appendage of fish and other aquatic organisms used for locomotion or balance.Yolk Sac: The first of four extra-embryonic membranes to form during EMBRYOGENESIS. In REPTILES and BIRDS, it arises from endoderm and mesoderm to incorporate the EGG YOLK into the DIGESTIVE TRACT for nourishing the embryo. In placental MAMMALS, its nutritional function is vestigial; however, it is the source of INTESTINAL MUCOSA; BLOOD CELLS; and GERM CELLS. It is sometimes called the vitelline sac, which should not be confused with the VITELLINE MEMBRANE of the egg.Dermatoglyphics: The study of the patterns of ridges of the skin of the fingers, palms, toes, and soles.Skates (Fish): The common name for all members of the Rajidae family. Skates and rays are members of the same order (Rajiformes). Skates have weak electric organs.Adrenarche: A stage of development at which the ADRENAL GLANDS undergo maturation leading to the capability of producing increasing amounts of adrenal androgens, DEHYDROEPIANDROSTERONE and ANDROSTENEDIONE. Adrenarche usually begins at about 7 or 8 years of age before the signs of PUBERTY and continues throughout puberty.Zona Reticularis: The inner zone of the adrenal cortex. This zone produces the enzymes that convert PREGNENOLONE, a 21-carbon steroid, to 19-carbon steroids (DEHYDROEPIANDROSTERONE; and ANDROSTENEDIONE) via 17-ALPHA-HYDROXYPREGNENOLONE.Adrenal Glands: A pair of glands located at the cranial pole of each of the two KIDNEYS. Each adrenal gland is composed of two distinct endocrine tissues with separate embryonic origins, the ADRENAL CORTEX producing STEROIDS and the ADRENAL MEDULLA producing NEUROTRANSMITTERS.Puberty, Precocious: Development of SEXUAL MATURATION in boys and girls at a chronological age that is 2.5 standard deviations below the mean age at onset of PUBERTY in the population. This early maturation of the hypothalamic-pituitary-gonadal axis results in sexual precocity, elevated serum levels of GONADOTROPINS and GONADAL STEROID HORMONES such as ESTRADIOL and TESTOSTERONE.Adrenal Cortex: The outer layer of the adrenal gland. It is derived from MESODERM and comprised of three zones (outer ZONA GLOMERULOSA, middle ZONA FASCICULATA, and inner ZONA RETICULARIS) with each producing various steroids preferentially, such as ALDOSTERONE; HYDROCORTISONE; DEHYDROEPIANDROSTERONE; and ANDROSTENEDIONE. Adrenal cortex function is regulated by pituitary ADRENOCORTICOTROPIN.Progesterone Reductase: An enzyme that catalyzes the reduction of a 3 beta-hydroxy-delta(5)-steroid to 3-oxo-delta(4)-steroid in the presence of NAD. It converts pregnenolone to progesterone and dehydroepiandrosterone to androstenedione. EC 1.1.1.145.Steroid 17-alpha-Hydroxylase: A microsomal cytochrome P450 enzyme that catalyzes the 17-alpha-hydroxylation of progesterone or pregnenolone and subsequent cleavage of the residual two carbons at C17 in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE. This enzyme, encoded by CYP17 gene, generates precursors for glucocorticoid, androgen, and estrogen synthesis. Defects in CYP17 gene cause congenital adrenal hyperplasia (ADRENAL HYPERPLASIA, CONGENITAL) and abnormal sexual differentiation.Models, Biological: 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.Pregnancy: The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.Animal Structures: Organs and other anatomical structures of non-human vertebrate and invertebrate animals.Dogfish: Sharks of the family Squalidae, also called dogfish sharks. They comprise at least eight genera and 44 species. Their LIVER is valued for its oil and its flesh is often made into fertilizer.Feathers: Flat keratinous structures found on the skin surface of birds. Feathers are made partly of a hollow shaft fringed with barbs. They constitute the plumage.WingForelimb: A front limb of a quadruped. (The Random House College Dictionary, 1980)Biological Science Disciplines: All of the divisions of the natural sciences dealing with the various aspects of the phenomena of life and vital processes. The concept includes anatomy and physiology, biochemistry and biophysics, and the biology of animals, plants, and microorganisms. It should be differentiated from BIOLOGY, one of its subdivisions, concerned specifically with the origin and life processes of living organisms.Audiovisual Aids: Auditory and visual instructional materials.Computer-Assisted Instruction: A self-learning technique, usually online, involving interaction of the student with programmed instructional materials.Charadriiformes: An order of BIRDS including over 300 species that primarily inhabit coastal waters, beaches, and marshes. They are comprised of shorebirds, gulls, and terns.Egg Shell: A hard or leathery calciferous exterior covering of an egg.Calcium Carbonate: Carbonic acid calcium salt (CaCO3). An odorless, tasteless powder or crystal that occurs in nature. It is used therapeutically as a phosphate buffer in hemodialysis patients and as a calcium supplement.Lubricants: Compounds that provide LUBRICATION between surfaces in order to reduce FRICTION.Animal Shells: The hard rigid covering of animals including MOLLUSCS; TURTLES; INSECTS; and crustaceans.Proto-Oncogene Proteins c-mos: 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.