When male ejaculates sperms during coitus of which for normal fertility at least……. percent sperms must have normal shape and size and at least ………..per cent of them must show vigorous motility

In humans, at the end of the first meiotic division, the male germ cells differentiate into the

Release of sperm from the seminiferous tubules is called

Arrange in correct sequence the structures formed during spermatogenesis

$(a)$ Spermatogonia

$(b)$ Secondary spermatocyte

$(c)$ Primary spermatocyte

$(d)$ Spermatid

Corpus luteum is a mass of cells found in