Page 876 - Atlas of Histology with Functional Correlations

4. After completing its function and regressing, the corpus luteum

transforms into:

A. an atretic follicle.

B. a new corpus luteum.

C. interstitial cells.

D. a corpus albicans.

E. lutein cells.

5. Decreasing levels of circulating hormones affect the endometrium by:

A. decreasing nutrient secretion of the uterine glands.

B. interrupting the flow of blood to the functionalis layer.

C. stopping the flow of blood to the basalis layer.

D. increasing the edema of the endometrium.

E. stopping the blood flow to the uterus.

ANSWERS

1. Correct Answer: D. To release hydrolytic enzymes from sperm to penetrate
the oocyte. This reaction allows the sperm to penetrate the surrounding cells

of the corona radiata and zona pellucida to fertilize the oocyte.

2. Correct Answer: A. Growth and resurfacing of the basalis layer to form a
new functionalis layer. When the functionalis layer is shed during menstrual
flow, the remnants of the uterine glands remain in the basalis layer that does
not lose its blood supply. During proliferative phase, the hormones

stimulate these cells to resurface the uterine wall and form a new
functionalis layer.

3. Correct Answer: B. The functionalis layer degenerates due to ischemia
(lack of blood supply). The spiral arteries in the functionalis layer are

sensitive to decreased hormonal levels and undergo constriction that
induces degeneration of this layer and its shedding during menstruation.

4. Correct Answer: D. A corpus albicans. This is a connective tissue scar that
forms after the functioning corpus luteum regresses and ceases to function.

5. Correct Answer: B. Interrupting the flow of blood to the functionalis layer.

The spiral arteries are very sensitive to the circulating levels of
progesterone and estrogen. When the circulating levels of these hormones

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