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• W2113575423 startingPage "379" @default.
• W2113575423 abstract "Patterns of chondrichthyan reproduction and development are diverse. Species either are reproductively active throughout the year, or have a poorly defined annual cycle with one or two peaks of activity, or have a well defined annual or biennial cycle. Based on embryological origin and adult morphology, their reproductive system is more similar to tetrapods than to teleosts. Primordial germ cells are of endodermal origin. The Wolffian ducts in males and Mullerian ducts in females become the functional urogenital ducts. Differentiation is under hormonal control. Unusual features of the reproductive system include an epigonal organ in males and females. It contains lymphoid and hemopoietic tissue. Leydig's gland, a modified region of the kidney, produces seminal fluid. In some species, sperm passing through the vas deferens, is enclosed in spermatophores. Rotating about their long axis, helical spermatozoa can move forward or reverse direction. Spermatogenesis often occurs in bicellular units, spermatocysts. These consist of a spermatogonium enclosed in a Sertoh cell. Fertilization is internal. Claspers, modified portions of the pelvic fins act as intromittent organs. In many viviparous sharks and rays, the female reproductive system is asymmetrical. Eggs of some sharks are the largest known cells. Yolk platelets contain lipovitellin. Oocytes have lampbrush chromosomes. Eggs released from the ovary into the body cavity are transported by ciliary action to the ostium of the oviduct. There they are fertilized. Physiological polyspermy is normal. The shell gland, a specialized region of the anterior oviduct, functions both in long term sperm storage and in egg case production. Egg cases of sharks and skates consist of unique collagenous protein with a 400 Å period, organized as a cholesteric liquid crystal. Chimaeroid egg cases contain 550 Å pseudotubules in orthogonal lattices. In small sharks, males copulate by coiling around the female. A parallel position is assumed by large sharks. Skates and rays copulate with ventral surfaces apposed or by a dorsal approach. Biting is a pre-copulatory release mechanism. Parental care, except for selective oviposition, is lacking. Heavily yolked eggs undergo meroblastic, discoidal cleavage. Development is lengthy, shortest (2–4 months) in rays, longer in skates (3–8 months) and longest (9–22 months) in sharks and chimaeras. Most sharks and all rays are viviparous. Chimaeras, skates, and some sharks are oviparous. Viviparity either involves a yolk sac placenta or is aplacental. If aplacental, the embryo derives nutrients either from yolk reserves, or by intra-uterine embryonic cannibalism, or from placental analogues which secrete “uterine milk.” Phylogenetic position, geographical distribution, benthic vs. pelagic habitat, adult size, egg-embryo size, feeding ecology, and embryonic osmoregulation are factors in the retention of oviparity or the evolution of viviparity." @default.
• W2113575423 created "2016-06-24" @default.
• W2113575423 creator A5068035315 @default.
• W2113575423 date "1977-05-01" @default.
• W2113575423 modified "2023-10-11" @default.
• W2113575423 title "Reproduction and Development in Chondrichthyan Fishes" @default.
• W2113575423 cites W133678739 @default.
• W2113575423 cites W1487398934 @default.
• W2113575423 cites W1503074147 @default.
• W2113575423 cites W1523656269 @default.
• W2113575423 cites W1543817181 @default.
• W2113575423 cites W1545014195 @default.
• W2113575423 cites W1859658990 @default.
• W2113575423 cites W1964775118 @default.
• W2113575423 cites W1967527670 @default.
• W2113575423 cites W1975833550 @default.
• W2113575423 cites W1976767193 @default.
• W2113575423 cites W1988944909 @default.
• W2113575423 cites W1993574687 @default.
• W2113575423 cites W1995131346 @default.
• W2113575423 cites W1997767479 @default.
• W2113575423 cites W1999897134 @default.
• W2113575423 cites W2006553424 @default.
• W2113575423 cites W2010955718 @default.
• W2113575423 cites W2011952939 @default.
• W2113575423 cites W2013203941 @default.
• W2113575423 cites W2014868197 @default.
• W2113575423 cites W2015972331 @default.
• W2113575423 cites W2018577034 @default.
• W2113575423 cites W2029516902 @default.
• W2113575423 cites W2030342237 @default.
• W2113575423 cites W2032982427 @default.
• W2113575423 cites W2033205314 @default.
• W2113575423 cites W2034229590 @default.
• W2113575423 cites W2037670181 @default.
• W2113575423 cites W2041697473 @default.
• W2113575423 cites W2049131787 @default.
• W2113575423 cites W2050039343 @default.
• W2113575423 cites W2052222972 @default.
• W2113575423 cites W2054662723 @default.
• W2113575423 cites W2056620065 @default.
• W2113575423 cites W2061051176 @default.
• W2113575423 cites W2061823074 @default.
• W2113575423 cites W2063372676 @default.
• W2113575423 cites W2064116993 @default.
• W2113575423 cites W2069902373 @default.
• W2113575423 cites W2070638065 @default.
• W2113575423 cites W2075269677 @default.
• W2113575423 cites W2080139859 @default.
• W2113575423 cites W2082633672 @default.
• W2113575423 cites W2087133665 @default.
• W2113575423 cites W2087480845 @default.
• W2113575423 cites W2094711496 @default.
• W2113575423 cites W2096018300 @default.
• W2113575423 cites W2099962365 @default.
• W2113575423 cites W2100634270 @default.
• W2113575423 cites W2101439589 @default.
• W2113575423 cites W2108655476 @default.
• W2113575423 cites W2110333253 @default.
• W2113575423 cites W2114069742 @default.
• W2113575423 cites W2130512601 @default.
• W2113575423 cites W2137124218 @default.
• W2113575423 cites W2158514519 @default.
• W2113575423 cites W2163342949 @default.
• W2113575423 cites W2254742311 @default.
• W2113575423 cites W2260363390 @default.
• W2113575423 cites W2265975574 @default.
• W2113575423 cites W2277334868 @default.
• W2113575423 cites W2278941004 @default.
• W2113575423 cites W2320314361 @default.
• W2113575423 cites W2321186217 @default.
• W2113575423 cites W2321424285 @default.
• W2113575423 cites W2322064585 @default.
• W2113575423 cites W2324612486 @default.
• W2113575423 cites W2331190356 @default.
• W2113575423 cites W2332442888 @default.
• W2113575423 cites W2334168477 @default.
• W2113575423 cites W2342432153 @default.
• W2113575423 cites W2418813867 @default.
• W2113575423 cites W2439001865 @default.
• W2113575423 cites W2735096270 @default.
• W2113575423 cites W280583467 @default.
• W2113575423 cites W2897123146 @default.
• W2113575423 cites W2897955617 @default.
• W2113575423 cites W3026020306 @default.
• W2113575423 cites W312062114 @default.
• W2113575423 cites W3186356463 @default.
• W2113575423 cites W356300578 @default.
• W2113575423 cites W362867815 @default.
• W2113575423 cites W564594173 @default.
• W2113575423 cites W612569900 @default.
• W2113575423 cites W147161519 @default.
• W2113575423 doi "https://doi.org/10.1093/icb/17.2.379" @default.
• W2113575423 hasPublicationYear "1977" @default.
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