Question

Given below are the steps which occur when an egg is not fertilised.

Arrange them in order.
A) Menstruation occurs.
B) Endometrium degenerates.
C) Progestrone production stops.
D) Corpus luteum degenerates into corpus albicans.

A. D -> C -> B -> A
B. A -> C -> D -> B
C. A -> D -> C -> B
D. A -> B -> C -> D

Answer 1

When an egg is not fertilized, the corpus luteum degenerates and progesterone production stops, leading to the breakdown of the endometrium and the onset of menstruation.

Step-by-step explanation:

The steps that occur when an egg is not fertilized in the human menstrual cycle are:

1. Corpus luteum degenerates into corpus albicans.
2. Progesterone production stops.
3. Endometrium degenerates.
4. Menstruation occurs.

In the absence of a fertilized egg, the corpus luteum which forms after the egg is released, degenerates. The progesterone and estrogen levels, both crucial for the maintenance of the endometrium, decrease. This leads to the breakdown of the endometrial lining of the uterus, resulting in menstruation as it is shed from the body. This restarts the menstrual cycle, priming the woman's body for a potential future pregnancy.