Withdrawal of which of the following hormones is the immediate cause of menstruation?
Progesterone
Estrogen
$FSH$
$FSH-RH$
Menstrual flow occurs due to lack of
Function of fertilizin is/are
Placenta is present in
The gestation period of elephants is about
Given below is a diagrammatic sketch of a portion of human male reproductive system. Which of the following part contributes to the maximum portion of semen?