Female Reproduction

Question 1

When does Oogenesis begin?

Answer 1

When female child is in utero

Question 2

What happens to cells in oogenesis?

Answer 2

• Some cells in embryonic ovary differentiate into Primary oocytes
• cells progress to prophase of meiosis I
• division arrests until sexual maturity (ie. at onset of puberty)

Question 3

When does ovulation begin?

Answer 3

At sexual maturity

Question 4

Ovulation’s impact on primary oocytes

Answer 4

Several primary oocytes stimulated every month by hormones to resume meiosis
- meiosis I resumes from prophase - results in asymmetric cell division so only 1 cell has all cytoplasm
- yields secondary oocyte
- other portion yields polar body

Question 4

What happens to secondary oocytes at ovulation?

Answer 4

• Continues to meiosis II
• meiosis II arrested at metaphase by cytostatic factor (CSF)

Question 5

When does completion of meiosis II occur?

Answer 5

At fertilization

Question 6

What happens at fertilization?

Answer 6

Second asymmetric division yields mature fertilized egg and a polar body