Question
When does oogenesis start in humans? Name the three hormones and their source, linked with oogenesis. How do they influence the process of oogenesis? Explain.
✓
Answer
Oogenesis starts during the embryonic developmental stages in the female foetus.
The hormones involved are:
- Follicle stimulating hormone (FSH)
- Luteinising hormone (LH).
- Progesterone.
- Follicle stimulating hormone (FSH):
- FSH stimulates the growth and development of ovarian follicles into a mature Graafian follicle.
- It also stimulates the secretion of estrogen from the follicle cells.
- Luteinising hormone (LH):
- LH stimulates the rupture of mature follicle and ovulation.
- It also stimulates the formation of corpus luteum from the ruptured follicle and secretion of progesterone from it.
- Progesterone:
- Progesterone is necessary to maintain the endometrium and implantation.
- In the absence of fertilisation, the corpus luteum degenerates and consequently the endometrium also degenerates leading to menstruation.
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