question_answer

Menstrual How occurs due to lack of

A)  progesterone   

B)  FSH

C)  oxytocin       

D)  vasopressin

Correct Answer: A

Solution :

In human female and other higher primates the regression of the endometrium is a more extreme process. The uterine lining rapidly deteriorates resulting in the rupture of its blood vessels, the flow of blood and other fluid and sloughing away of most of endometrium. This phenomenon is collectively called menstruation. Menstrual flow occurs due to lack of progesterone secreted from corpus luteum. Oxytocin and Vasopressin (ADH) are secreted from posterior lobe of pituitary. Oxytocin promotes contraction of uterine .muscles and contraction of myoepithelial cells of the lactating breast, squeezing milk into large duct. ADH increases the reabsorption of water in the nephron of kidney.