Which of the following hormone levels will cause release of ovum (ovulation) from the graafian follicle? (NEET 2020)
Answer: (C) High concentration of Estrogen. Answer: (C) High concentration of Estrogen Solution: NCERT states that during the follicular phase the growing follicles secrete estrogens, both LH and FSH attain a peak in mid-cycle, and the rapid LH surge induces rupture of the Graafian follicle and ovulation.
- A.Low concentration of LH
- B.Low concentration of FSH
- C.High concentration of Estrogen✓
- D.High concentration of progesterone
Correct Answer
(C) High concentration of Estrogen
Solution & Explanation
Answer: (C) High concentration of Estrogen Solution: NCERT states that during the follicular phase the growing follicles secrete estrogens, both LH and FSH attain a peak in mid-cycle, and the rapid LH surge induces rupture of the Graafian follicle and ovulation. Among the given options, ovulation is associated with high (peak) levels rather than low levels; the high estrogen secreted by mature follicles in mid-cycle triggers the LH surge that causes ovulation, so option C is the best NCERT-supported choice (low LH/FSH and high progesterone do not cause ovulation). Answer is NCERT-grounded as the 2020 paper had no printed biology key. NCERT Reference: Ch 2, p.35, line 5 — "estrogens by the growing follicles. Both LH and FSH attain a peak level"