primary oocyte and secondary oocyte...when are these made?

[sangria1986]

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I have conflicting information on when primary and secondary oocytes are made....this is what i have so far...

the primary oocyte is made in fetus through replication (s phase) from oogonium which come from oogonia (stem cells)

at puberty primary oocyte goes through meiosis 1 and becomes secondary. secondary remains as is until penetrated by sperm and then goes through second meiosis to become ovum. I'm confused...is this right?

 

[Rabolisk]

Right. More specifically, meiosis I halts at prophase, and meiosis II halts at metaphase.

 

[Chocolatebear89]

Also, does mitosis end at birth, so females have a definite number of eggs when they are born?

Does meiosis occur from birth to puberty or starting at puberty?

 

[sangria1986]

Also, does mitosis end at birth, so females have a definite number of eggs when they are born?

Does meiosis occur from birth to puberty or starting at puberty?

yes females have a set number of eggs. mitisos ends at birth, the whole process stops at prophase 1 of meiosis at birth. NOTHING happens until puberty.

 

[plzNOCarribbean]

Wait, so a fertilized egg that is predestined to be a girl already has a set number of eggs that she will have for her lifetime before she is born. And leading up to her birth, these oogonium are all undergoing MITOSIS to become primary oocytes?

2)then AFTER the girl is born, the primary oocytes undergo meiosis I and are arrested in Prophase I?? is this right?

3) and then after the girl reaches puberty and begins her menstrual cycle is when each month, only one of these primary oocyes that are arrested become secondary oocytes in the overies PRIOR to OVULATION??

is it correct that after ovulation, the secondary oocyte is in the fallopian tubes and this is where, if fertilized, (AND ONLY IF FERTILIZEd?) the secondary oocyte will undergo meiosis II and become a zygote?--basically, what i'm asking is the second meiotic division to turn the secondary oocyte into the zygote doesn't occur unless the secondary oocyte is fertilized?

IM sorry i know that was sooooo long but I thought I had reproduction down and ive been looking at diagrams on google and they all seem to depict this rocess differently. any clarification would be GREATLY appreciated. 😀

heres the diagram I was looking at
http://faculty.stcc.edu/AandP/AP/AP2pages/reprod/oogenesi.htm