Fertilization

Question 1

steps of acrosome reaction

Answer 1

-penetration of cumulus granulosa cells
-fusion of plasma membrane and outer acrosomal membrane
-penetration of ZP

Question 2

function of ZP-1

Answer 2

structural support and integrity for ZP(innermost layer)

Question 3

function of ZP-2

Answer 3

helps acrosome reacted sperm move through zona(middle layer)

Question 4

function of ZP-3

Answer 4

zona protein binds to receptor on sperm plasma to induce acrosome reaction(outermost layer)

Question 5

importance of ZP layers for fertilization(most to least)

Answer 5

ZP-3
ZP-2
ZP-1

Question 6

accessory sperm definition

Answer 6

sperm bound to ZP that dont fertilize

Question 7

methods preventing polyspermy and what animals have them

Answer 7

-zona reaction: cow, pig
-Vitelline block: rabbit
-both: rats, mice

Question 8

steps of zona reaction/vitellin block

Answer 8

-initiated by sperm penetration
-exocytosis of cortical granules into perivitelline space
-reorganization of zona and vitellin membrane

Question 9

components of reorganization of zona and vitellin space(steps of zona reaction/vitellin block)

Answer 9

-enzyme released to harden ZP
-ZP-3 sperm receptors inactivated
-efficiency decreased by age and temperature

Question 10

when does oocyte resume meiosis II

Answer 10

after fertilization

Question 11

where do male and female pronuclei migrate towards

Answer 11

syngamy(the center)

Question 12

how does to sperm cell form the male pronuclei

Answer 12

-decondensation of DNA
-replacement of protamines with histones