$A$ temporary endocrine gland formed after ovulation in the ovary is:

Define the following terms:
$(1)$ Spermiogenesis
$(2)$ Zona pellucida

In humans,what is the ratio of the number of gametes produced from one male primary sex cell to the number of gametes produced from one female primary sex cell?

The longest phase of spermatogenesis is......

Identify the location of mitochondria in a human sperm.

In human females,the number of primary follicles left in each ovary at puberty is