Ch 2 Flashcards
Today, over ___% of all infants are born in the U.S. every year are conceived using ART.
1%
___% of couples conceive within 2 years of trying.
92%
Male causes of failing fertilization
failure to produce sufficient number of healthy sperm and tubal blockages
female causes of failing fertilization
failure to produce sufficient numbers of healthy eggs and tubal blockages
head section of human sperm contains..
sperm cell membrane, acrosome, pronucleus
midpiece sectioon of human sperm contains…
midpiece
tail section of human sperm contains…
flagellum
spermatogonia
male germ cells
what do spermatogonia do?
line the outer walls of the seminiferous tubles and generate primary spermatocytes
what do primary spermatocytes undergo?
meiosis
self-renewing stem cells
undergo mitosis to replace those spermatogonia that are continuously being lost to meiosis
spermatogonia are what kind of cells?
self-renewing stem cells
oocytes
immature eggs
when do women produce all of their oocytes?
before they are born
what do all oogonia do in Meiosis I?
either die or commit to oogenesis and arrest
how many oocytes survive to wait from puberty to fertilization?
500,000
follicles
where oocytes mature within the ovary
cumulus cells
follicle cells associated with the egg after ovulation
the oocytes are stored in the ____ and mature within the ____ of the ovary.
ovary; follicles
4 steps of fertilization
localization, penetration, prevention of polyspermy, pronuclear fusion
steps of localization
a) uterine contractions move sperm up the oviduct b) near the finish line – strong swimming by the sperm
steps of penetration
a) capacitation of sperm to reach zona pellucida b) acromosome reaection - penetrate zona pellucida
what is required for the sperm to penetrate the cumulus layer and reach the zona pellucida?
capacitation of sperm
acrosome reaction
release of enzymes by the sperm to penetrate the zona pellucida