What is the main function of the breast?

• A. Milk secretion during lactation
• B. Immune defense
• C. Fat storage
• D. Temperature regulation

Answer: (A)

Milk production and secretion during lactation is the primary function of the breast. The glandular tissue within the breast forms lobules with milk-producing alveolar cells that synthesize milk in response to hormones like prolactin. After birth, prolactin maintains milk production, and oxytocin triggers the ejection of milk by stimulating contraction of the myoepithelial cells around the alveoli, allowing the infant to feed.

Breast milk also offers immune protection due to antibodies and immune cells it contains, which is a beneficial byproduct of lactation, not the main purpose. Fat storage is a secondary characteristic of breast tissue, and temperature regulation is not a primary role.