What is testis and wnat is overy how zygote form

hope this helps u

Explanation:

One of two egg-shaped glands inside the scrotum that produce sperm and male hormones is called testis.

One of a pair of female glands in which the eggs form and the female hormones estrogen and progesterone are made.

A zygote forms when a sperm penetrates the outer surface of an egg.

the diploid number of chromosomes is sometimes represented by the symbol 2n. for the fruit fly, the diploid number is 8, which can be written as 2n = 8, where n represents twice the number of chromosomes in a sperm or egg cell.