Exam Flashcards
(301 cards)
How are sperm released in isthmus?
Capacitation
what is capacitation
biochemical changes that cause destabilisation of the sprem membrane
when does capacitation occur
ass soon as they are in the female reproductive tract
what is hyperactive motility
shift in flagellar movement from progressive linear to accelerated excited
how is sperm guided to oocyte
thermotaxis and chemotaxis
what is acrosome reaction
release of enzymes after membrane fusion which allows sperm to penetrate zona pellucida
where does fertilisation occur
perivitelline space
steps in oocyte activation (4)
increase in intracellular ca
cortical reaction
resumption of meiosis
decondensation of sperm nucleus
what is cortical reaction and why is it good
exocyotosis of cortical granules in to perivitelline space. it causes a change in zona pellucida so sperm cannot enter
purpose of cortical reaction
prevention of polyspermy
what is superfecundation
fertilisation of 2 or more ova from same cycle, separate from acts of intercourse (in bitches and queens)
fertile life of sperm in cow
28-50h
fertile life of sperm in mare
144h
fertile life of sperm in bitch
144h
fertile life of sperm in sow
36h
what is spermatogenesis
process by which spermatozoa are formed
where does spermatogenesis occur
seminiferous tubules
puberty age bull
10-12 months
puberty age stallion
13-18 months
puberty age dog
5-10 months
puberty age boar
4-8 months
puberty age ram
4-6 months
purpose of leydig cells
interstitial
have LH receptors
produce testosterone
purpose of sertoli cells
supportive cells
remove excess cytoplasm from spermatids
produce estradiol, inhibin and antimullerian hormone