Question

What is lactation? Name the hormone that is principally involved in milk synthesis and secretion.

Answer 1

Lactation:

1. The process of synthesis of human milk or milk secretion from a mother's mammary glands shortly after birth is called lactation.
2. The milk produced provides nourishment and immunity to the young.

Prolactin:

1. Prolactin is required for milk secretion by the cells of the alveoli, as this hormone is principally involved in milk synthesis and secretion.
2. The levels of prolactin in the blood rise significantly during pregnancy, stimulating the growth and development of breast tissue in preparation for milk production.
3. However, milk is not produced because of progesterone and estrogen, which are the hormones of pregnancy, that block this action of prolactin.
4. After childbirth, progesterone and estrogen levels drop rapidly, prolactin is no longer blocked, and milk secretion begins.