Question

Given below are two statements:
Statement I: Ovulation is caused by LH surge leading to rupture of Graafian follicles.
Statement II: Graafian follicle remaining after ovulation transform into corpus luteum and secretes large amount of estrogen.
In the light of the above statements, choose the most appropriate answer from the options given below:

• A. Statement I is incorrect but Statement II is correct
• B. Both Statement I and Statement II are correct
• C. Both Statement I and Statement II are incorrect
• D. Statement I is correct but Statement II is incorrect

Hint:

Progesterone is known as the "pregnancy-maintaining hormone" because it is secreted in large amounts by the corpus luteum during the luteal phase. Estrogen levels peak twice: once before ovulation (follicular phase) and once moderately during the luteal phase.

Answer 1

The Correct Option is D

Step 1: Read both statements.
Statement I says ovulation is caused by an LH surge that ruptures the Graafian follicle. Statement II says the leftover follicle becomes the corpus luteum and secretes large amounts of estrogen.
Step 2: Recall the mid-cycle event.
Around day 14, LH rises sharply to a peak called the LH surge, and this surge triggers ovulation by rupturing the mature Graafian follicle.
Step 3: Judge Statement I.
Since the LH surge truly causes the follicle to rupture and release the oocyte, Statement I is correct.
Step 4: Recall what the corpus luteum does.
After ovulation the ruptured follicle changes into the corpus luteum, whose main secretion is progesterone, needed to maintain the endometrium.
Step 5: Judge Statement II.
Statement II claims it secretes large amounts of estrogen, but the major hormone is progesterone, so Statement II is incorrect.
Step 6: Combine the verdicts.
Statement I is correct and Statement II is incorrect, which is option 4.
\[ \boxed{\text{Statement I is correct but Statement II is incorrect}} \]