Question

Select the option that shows correct statements :
(i) Corpus luteum secretes progesterone.
(ii) Only FSH attains a peak level in middle of cycle.
(iii) LH surge induces rupture of graafian follicle.
(iv) Luteal phase of menstrual cycle is also called proliferative phase.

• A. Only (ii) is correct.
• B. (i) and (iii) are correct.
• C. Only (iv) is correct.
• D. (ii) and (iv) are correct.

Hint:

Remember the synonyms for the phases:
Follicular Phase = Proliferative Phase.
Luteal Phase = Secretory Phase.
This is a frequent point of confusion in exams.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
The human menstrual cycle is regulated by pituitary hormones (LH and FSH) and ovarian hormones (estrogen and progesterone).
Understanding the timing of these hormone peaks and the functions of structures like the corpus luteum is essential for identifying the correct statements.
Step 2: Detailed Explanation:
Let us evaluate each statement based on physiological facts:
(i) Corpus luteum secretes progesterone: After ovulation, the ruptured Graafian follicle transforms into the corpus luteum, which acts as a temporary endocrine gland and secretes large amounts of progesterone to maintain the uterine lining. This statement is correct.
(ii) Only FSH attains a peak level in middle of cycle: This is incorrect. Both LH (Luteinizing Hormone) and FSH (Follicle Stimulating Hormone) attain a peak level in the middle of the cycle (around day 14).
(iii) LH surge induces rupture of graafian follicle: The rapid secretion of LH leading to its maximum concentration during the mid-cycle is called the LH surge. It induces the rupture of the Graafian follicle and thereby the release of the ovum (ovulation). This statement is correct.
(iv) Luteal phase of menstrual cycle is also called proliferative phase: This is incorrect. The luteal phase is also known as the secretory phase. The proliferative phase is another name for the follicular phase.
Since statements (i) and (iii) are correct, the correct option is (B).
Step 3: Final Answer:
Statements (i) and (iii) are the only correct statements among the given choices.