The fusion of a sperm from the father and an ovum from the mother is called .

Sperm production occurs within the slender, tightly coiled .

The male gonads are the .

The physical transformation of a spermatid to a spermatozoon is called .

After passing along the tail of the epididymis the spermatozoa arrive at the .

The primary energy source for the mobilization of sperm is .

A peptide hormone that causes the secretion of androgens by the interstitial cells of the testes is .

The female gonads are the .

The reddish-brown coloration surrounding the nipples of the breasts is referred to as the .

The principal hormone that prepares the uterus for pregnancy is .