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8 Cards in this Set

  • Front
  • Back
filtered toad semen devoid of sperm would not fertilize eggs
(but then concluded that viscuous fluid on paper was driving force for fertilization)
JL Prevost & JB Dumas
1. sperms are not parasites, active agents in fertilization
2. universal existence of sperm in sex mature males and absence immature, aged and mule. sperm entered egg
A Von Kolliker
formation of sperm fr cells in testes, believed no physical contact between sperm and egg. sperm excited egg to develop
meditteranean sea urchin (toxopneustes lividus), observed sperm entering egg and 2 nuclei unite
same as Hertwig, detailed mechanism of sperm entry
demonstrated that eggs of cnidarian Orthopyxis caliculata-secrete+regulate timing of release of chemotactic factor
-no attraction to eggs who has not completed 2nd meiotic division
-sperm migrate towards egg after meiotic division
Smith and Suarez
uncapacitated sperm binds to membrane of oviduct cells located at the ampulla
Ralt and Co.
experiment using follicular fluid of human similar to sea urchin experiment-drop of this to slide, saw some sperm stop and go towards drop