egg undergoes meiosis, which is formation, at the same time she's maturing (called oogenesis)
- formation and maturing are happening simultaneously
In oogenesis, what happens with the egg?
egg gets bigger and bigger because she has to bring structures for early development due to the fact that the fertilized egg and early embryo don't turn on the zygotic genome at first
In males, explain gametogenesis.
two events that take place (not two different process) at different times
Gametogenesis is made up of spermatogenesis, which is formation, and spermeogenesis, which is maturation
Explain the sperm cell at the end of spermatogenesis.
at the end, the cell doesn't look like a sperm, but it is haploid. Spermeogenesis must change it anatomically to resemble sperm
Explain sperm at the end of gametogenesis.
sperm is very small to what it orignally was
Function: to bring haploid nucleus to egg only
Very little cytoplasm
Whereas the female has structures, the sperm loses material.
Explain a similarity of gametogenesis in both males and females.
both rely on pituitary hormones
The anterior pituitary makes lots of hormones: FSH and LH, both of which are necessary for gametogenesis in Females and Males
Male Gametogenesis:
When does stuff begin to happen?
nothing happens in testes until puberty; sperm not produced prior to puberty.
From puberty on, spermatogenesis and spermiogenesis are continuous until the end of sexual life.= constantly making sperm
What is the set date for male gametogenesis?
no set date
i slows down, but doesn't stop like females with menopause
no end, but decreases with age
In females, when does gametogenesis begin to happen?
One process (formation and maturation): begins process when in mom's uterus; still an embryo
every stem cell (oogonia) in follicle commits to meiosis at the same time
All are made; She has no oogonia at birth
All begin Meiosis I while she is still in womb
Stops at birth and doesn't start again till puberty (once a month; not continuous)
Set end for female gametogenesis?
menopause
- no longer produces viable gametes
Difference in terms of products of cells in male and female gametogenesis.
four sperm at end of gametogenesis (one spermatophyte makes four sperm)
one primary oocyte makes one egg
Cell you will find in testes all the time is the __.
spermatogonium
What is the spermatogonium?
diploid cell/ provides cells that will give rise to sperm
it is the stem cell or the primordial germ cell: cell that will give rise to gametes
produces trillions of sperm
True or False: Not every spermatogonium will commit to Gametogenesis.
true
A male always has __ and they always divide __.
spermatogonium
mitotically
a.If he is going to make a sperm, some __have to commit to __, which means they __ i.When they commit to meiosis, changes take place= __
b.Part of commitment is __; cant go back and divide __; committed
spermatogonia
meiosis
no longer divide mitotically
primary spermatocyte
replication
mitotically
\ 1.Cell that begins Gametogenesis in the male is the primary __, not the __
spermatocyte
spermatogonium
Which is the uncommitted stem cell?
Which is the committed one?
