Question

research has determined that pcos patients have twice the number of follicles than women without pcos, however most are underdeveloped.
the graph below summarizes some of the data collected by researchers while investigating pcos.

16 which statement identifies evidence that supports the claim that pcos is the result of a failure of a feedback mechanism associated with the egg cell?
(1) patients with pcos do not experience the peak in fsh production that women without pcos do, disrupting their menstrual cycle.
(2) patients with pcos have a lower level of lh, so ovulation does not occur.
(3) progesterone and lh levels in women with pcos remain elevated after day 14, resulting in irregularities in the menstrual cycle.
(4) the levels of estrogen and fsh in women with pcos are elevated, resulting in the overdevelopment of follicles present.

Explanation:

Analyze the question prompt

The question asks for evidence supporting the claim that PCOS is the result of a failure of a feedback mechanism associated with the egg cell (follicle development).

Examine the provided graph

The graph shows hormone levels in women with PCOS over a 28-day cycle:

• Estrogen (dotted line) is highly elevated throughout the first half of the cycle.
• FSH (solid line) shows a peak around day 14.
• LH (dash-dot line) is relatively flat/low.
• Progesterone (dashed line) remains very low throughout the cycle.

Evaluate the options

• Option (1) states patients with PCOS do not experience the peak in FSH. However, the graph clearly shows a distinct peak in FSH (solid line) around day 14. Thus, this is incorrect.
• Option (2) states patients have a lower level of LH, so ovulation does not occur. While LH is low, ovulation and the egg cell's release are directly tied to the feedback loop of follicle development (which produces estrogen) and FSH/LH.
• Option (3) states progesterone and LH remain elevated after day 14. The graph shows both progesterone and LH are very low after day 14, so this is incorrect.
• Option (4) states that the levels of estrogen and FSH in women with PCOS are elevated, resulting in the overdevelopment of follicles present. The introductory text states PCOS patients have twice the number of follicles, but most are underdeveloped. Elevated estrogen (shown as a very high peak in the graph) and FSH levels stimulate follicle growth, but the failure of the feedback mechanism prevents proper maturation and ovulation of a single egg cell, leading to many underdeveloped follicles.

Answer:

• (1) Patients with PCOS do not experience the peak in FSH production that women without PCOS do, disrupting their menstrual cycle.
• (2) Patients with PCOS have a lower level of LH, so ovulation does not occur.
• (3) Progesterone and LH levels in women with PCOS remain elevated after day 14, resulting in irregularities in the menstrual cycle.
• (4) The levels of estrogen and FSH in women with PCOS are elevated, resulting in the overdevelopment of follicles present. (Correct answer)