The Mammalian Corpus Luteum and its Function

The mammalian corpus luteum is a temporary endocrine structure that forms in the ovary after ovulation. It plays a crucial role in the reproductive system by producing hormones that are necessary for the maintenance of pregnancy.

Formation of the Corpus Luteum
1. Ovulation: During the menstrual cycle, an egg is released from the ovary in a process called ovulation.
2. Ruptured follicle: After ovulation, the ovarian follicle from which the egg was released transforms into the corpus luteum.
3. Corpus luteum formation: The ruptured follicle collapses and fills with blood, forming a yellowish structure called the corpus luteum.

Function of the Corpus Luteum
The corpus luteum produces two key hormones: progesterone and a small amount of estrogen. These hormones are essential for maintaining pregnancy and preparing the uterus for implantation of a fertilized egg.

1. Progesterone Production
- Progesterone is the primary hormone produced by the corpus luteum.
- It prepares the uterus for pregnancy by thickening the uterine lining, making it more receptive for implantation.
- Progesterone also inhibits uterine contractions, preventing premature labor.
- It promotes the growth of blood vessels in the uterine lining, ensuring proper blood supply to the developing fetus.
- Progesterone also suppresses the immune response, preventing the body from rejecting the embryo.

2. Estrogen Production
- While the corpus luteum produces a small amount of estrogen, the ovaries are the main source of this hormone.
- Estrogen works in conjunction with progesterone to support the development of the uterine lining.
- It also plays a role in the growth and development of the fetus, particularly in the early stages of pregnancy.

Other Hormones
The mammalian corpus luteum does not produce luteotropic hormone or luteinizing hormone. Luteotropic hormone, also known as prolactin, is produced by the anterior pituitary gland and is involved in milk production after childbirth. Luteinizing hormone is released by the anterior pituitary gland and plays a role in the menstrual cycle by stimulating ovulation.

Therefore, the correct answer is option 'B' - The mammalian corpus luteum produces progesterone, which is essential for maintaining pregnancy and preparing the uterus for implantation.