Human Reproduction Question 64

64. Which of the following hormones is responsible for both the milk ejection reflex and the foetal ejection reflex?

(a) Relaxin

(b) Oestrogen

(c) Prolactin

(d) Oxytocin

Show Answer

Answer : d

Hints & Solutions

(d) Foetal ejection reflex triggers release of oxytocin from the maternal anterior pituitary gland. Oxytocin acts on the uterine muscles and causes stronger uterine contractions. Milk ejection reflex is caused by combined neurogenic and hormonal reflexes that involve release of oxytocin from posterior pituitary gland. Relaxin, secreted by the ovary and placenta, causes the cervix to dilate and prepares the uterus for the action of oxytocin during labour. Oestrogen, secreted from ovary, is responsible for the development and regulation of the female reproductive system and secondary sex characteristics. Prolactin, secreted from anterior pituitary, stimulates breast development and milk production in women.