Question

question 21
which hormone is involved in the initiation of the let down reflex triggered by infant suckling?
progesterone
estrogen
prolactin
oxytocin

Explanation:

The let - down reflex is a physiological process in lactation. Oxytocin is the hormone that causes the contraction of the myoepithelial cells in the breast, leading to milk ejection in response to infant suckling. Progesterone is mainly involved in pregnancy maintenance (e.g., preparing the endometrium for implantation). Estrogen has roles in sexual development and the menstrual cycle. Prolactin is responsible for milk production (lactogenesis), not the let - down reflex.

Answer:

Oxytocin