Question

In the let-down reflex, which structure's contraction directly results in the ejection of milk from the alveoli?

Options

• Myoepithelial cells surrounding alveoli

• Nipple tissue

• Mammary tubules

• Lactiferous ducts

Answer 1

During the let-down reflex, oxytocin causes myoepithelial cells surrounding the alveoli to contract. This contraction squeezes the milk from the alveoli, forcing it through the mammary tubules, mammary ducts, ampulla, lactiferous ducts, and finally out through the nipple.