Questions: Multiple Choice Question Which of the following is the role of prolactin (PRL)? It regulates the water concentration of body fluids. It contracts muscles associated with milk-secreting glands. It sustains milk production after birth. It stimulates cell growth and replication. Need help? Review these concept resources.

The answer is the third one: It sustains milk production after birth.

Explanation for each option:

1. It regulates the water concentration of body fluids.

   • This is incorrect. The regulation of water concentration in body fluids is primarily the role of antidiuretic hormone (ADH), not prolactin.

2. It contracts muscles associated with milk-secreting glands.

   • This is incorrect. The contraction of muscles associated with milk-secreting glands is primarily the role of oxytocin, which helps in milk ejection during breastfeeding.

3. It sustains milk production after birth.

   • This is correct. Prolactin is a hormone produced by the anterior pituitary gland that plays a crucial role in maintaining milk production in the mammary glands after childbirth.

4. It stimulates cell growth and replication.

   • This is incorrect. While prolactin has various roles, the primary hormone responsible for stimulating cell growth and replication is growth hormone (GH).

In summary, prolactin's primary role related to the options given is to sustain milk production after birth.