Question

The main function of mammalian corpus luteum is to produce
A) Progesterone
B) Estrogen
C) Relaxin
D) Human chorionic gonadotropin

Answer 1

During the follicular phase primary follicles developed into the secondary follicles and subsequently the mature graafian follicle. A corpus luteum is a mass of cells in an ovary formed from the rupture of a Graafian follicle after ovulation; its role depends upon whether or not fertilization occurs.

Complete answer:
The Corpus luteum secretes large amounts of progesterone which is essential for the maintenance of the endometrium which is thickened by estrogen.

In the luteal phase, maintenance of endometrium by progesterone is necessary for implantation of the fertilized ovum and maintenance of pregnancy.

During pregnancy all the events of the menstrual cycle stop and there is no menstruation due to the high level of progesterone, it allows the uterus to grow without having contractions, improves blood flow and oxygen supply.

The corpus luteum starts decreasing in size at around 10 weeks of pregnancy. If fertilization or implantation do not occur, then the corpus luteum begins to break down. This causes a decline in progesterone as well as estrogen levels, which leads to the start of another menstrual cycle.

Estrogen: It is secreted by follicles (mainly) and a small amount through the Corpus luteum and adrenal glands. This hormone stimulates the uterine endometrial epithelial to enlarge, become more vascular and more glandular.

Relaxin: It is also produced by the corpus luteum in both pregnant and non-pregnant women but it is also produced by decidua and placenta. In males, it is synthesized in the prostate gland.

Human chorionic gonadotropin: It is synthesized by the placenta which stimulates the corpus luteum of pregnancy to continue to secrete progesterone for a long time after its normal lifetime.

So, the correct answer is “Option A”.

Note:
Corpus luteum is a temporary endocrine structure, it involves ovulation and early pregnancy. The Corpus luteum secretes other hormones as well but its main function is to produce progesterone, and also progesterone is secreted by other sources as well but its main source is corpus luteum. Progesterone is a steroid hormone that belongs to the group progestogens and it is the major progestogen in the human body.