Question

Choose the option that shows the correct sequence of various events occurring during the menstrual cycle.
I) Rapid secretion of Luteinizing hormone (LH)
II) Decrease in the level of progesterone and estrogen
III) Release of FSH under the influence of GnRH
IV) Corpus luteum begins to secrete progesterone and estrogen

• A. III \(\rightarrow\) II \(\rightarrow\) I \(\rightarrow\) IV
• B. III \(\rightarrow\) I \(\rightarrow\) IV \(\rightarrow\) II
• C. II \(\rightarrow\) I \(\rightarrow\) IV \(\rightarrow\) III
• D. I \(\rightarrow\) III \(\rightarrow\) II \(\rightarrow\) IV

Hint:

FSH release comes first, then the LH surge, then corpus luteum activity, then fall of hormones.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept
The menstrual cycle follows a fixed hormonal sequence.

Step 2: Order of events
III: GnRH causes release of FSH, which develops follicles.
I: rising estrogen causes a surge of LH at mid-cycle and ovulation.
IV: the corpus luteum secretes progesterone and some estrogen.
II: without fertilisation, the corpus luteum degenerates and hormone levels fall.

Step 3: Conclusion
The sequence is III, I, IV, II.

Final Answer:
The sequence is III, I, IV, II. \[ \boxed{\text{(B) }\text{III}\rightarrow\text{I}\rightarrow\text{IV}\rightarrow\text{II}} \]