Chemical Coordination And Regulation Ques 71

71. Which one of the following hormone stimulates the “let-down” (release) of milk from the mother’s breasts when the baby is sucking ?

[1996]

(a) Progesterone

(b) Oxytocin

(c) Prolactin is a hormone produced by the anterior pituitary gland that primarily stimulates milk production in the breasts after childbirth. It also plays roles in regulating the immune system, stress response, and reproductive functions.

(d) Relaxin

Show Answer

Answer : b

Hints & Solutions

(b) Prolactin is a proteinaceous hormone released by anterior lobe of pituitary. Prolactin supplements the action of gonadal hormones in stimulating the growth and activity of female mammary gland during pregnancy and lactation. Oxytocin released by the posterior lobe of pituitary gland, is important for the mechanism of ejection of milk from the mammary glands due to sucking of breasts by infant. Progesterone, released by corpus luteum brings about pregnancy changes such as uterine growth, implantation of embryo etc. Relaxin is a proteinaceous hormone secreted by corpus luteum towards the end of gestation period for loosening and softening of pelvic ligaments, relaxing of uterus for easing parturition.