036 Hormonal Control of Reproduction

Question 1

Why can leptin act as a marker for GnRH secretion?

Answer 1

Because fat = source of oestrogen

also it indicates enough adiposity for ovulation

Question 2

How often are pulses of FSH and LH during puberty

Answer 2

every 90 minutes

Question 3

Which hormones stimulate spermatogenesis

Answer 3

Testosterone and FSH

Question 4

Where are sertoli cells located?

Answer 4

In the seminiferous tubules

Question 5

What are inhibins?

Answer 5

Inhibit FSH release (and less so LH)

Question 6

Describe the process of sperm formation?

Answer 6

1. Spermatogoonia remain as precursor stem cell until puberty
2. Mitosis into more spermatogonium as stem cells
3. Differentiate into primary spermatocytes
4. Undergoes meiotic replication to secondary spermatocytes in meiosis I
5. Undergoes meiosis II to form late spermatids (still linked)
6. Spermatids differentiate into spermatozoa by spermiogenesis

Question 7

Describe the follicle development

Answer 7

Primodial follicle –> primary follicle –> secondary follicle –> mature graafian follicle –> release corona radiata containing secondary oocyte, –> degenerates into corpus luteum.

If fertlisation doesnt occur, it becomes corpus albicans

Question 8

Which hormones will be very high after menopause?

Answer 8

FSH, LH

Question 9

Describe process of oogenesis

Answer 9

1. Oogonium begins meiosis in fetal development
2. mitotic division into primary oocyte
3. after puberty, primary oocyte complete meiosis I and differentiate into secondary oocyte and 1st polar body.
4. at ovulation, secondary oocyte begins meiosis II to form secondary oocyte
5. Only after fertilisation does meiosis II complete, forming second polar body.