The growth and differentiation of primordial follicles is under the control of which hormone?
FSH
FSH (follicle stimulating hormone) controls the growth and differentiation of ovarian follicles. This anterior pituitary glycoprotein acts on FSH receptors on granulosa cells, driving their proliferation through the primary, preantral and antral stages, inducing antral fluid formation, and critically inducing aromatase, which converts theca-derived androgens to oestradiol — the essence of the two-cell two-gonadotropin theory. FSH also induces LH receptors on the dominant follicle. The intercycle FSH rise, caused by falling luteal oestradiol, progesterone and inhibin A, recruits each new cohort; the follicle richest in FSH receptors becomes dominant while the rest undergo atresia.
Why the others are wrong: LH acts on theca cells to make androgen precursors and its mid-cycle surge triggers ovulation and luteinisation, not early follicular growth. Growth hormone, via IGF-1, only amplifies the granulosa response to FSH and is an ART adjuvant. Progesterone is a corpus luteum product that prepares the endometrium and suppresses GnRH pulsatility, thereby inhibiting follicular development.
Key point: FSH acts on granulosa cells (aromatase, oestrogen, follicular growth); LH acts on theca cells and triggers ovulation.
Similar Questions
Consider the following statements with respect to endometrial cycle:
1. The basal zone is uninfluenced by any hormone.
2. Saw-toothed glandular epithelium is seen in secretory phase.
3. Stratum compactum contains mainly the glands and less stroma.
4. Pseudostratification is seen in proliferative phase of menstrual cycle.
Which of the statements given above are correct?
When does the secondary oocyte complete the second meiotic division?
Which one of the following statements explains self-priming of gonadotrophs?
Important Questions from Physiology of Menstruation & Fertilization
- Implantation of a fertilised ovum occurs on which day following fertilisation?
- Withdrawal bleeding following administration of progesterone in a case of secondary amenorrhea indicates all EXCEPT:
- Diagnostic criteria for PCOD are:
1. Oligo/amenorrohoea
2. Hyperandrogenism
3. Polycystic ovaries on ultrasound
Which of the above are correct? An 18 year old unmarried girl comes with complaints of heavy, prolonged bleeding during menses. Which among the following investigations is NOT usually advised?
- Which one of the following is true about Basal body temperature?
1. Biphasic pattern
2. Increase in the level of progesterone and norepinephrine
3. Temperature falls by $0.5^{\circ}C$ after ovulation
4. It can predict ovulation precisely
Select the correct answer using the code given below:
