One gamete is formed during:

Crossing over

Oogenesis

Spermatogenesis

Sexual reproduction

One gamete is formed during:

Spermatogenesis

Explanation:

This involves development of an haploid spermatozoa resulting from germ cell

Answer: Oogenesis

Explanation:

Oogenesis is a process in female reproductive system in which a matured ovum is formed from egg cell.

In human reproductive system one mature ovum is produced from four haploid cells during meiosis. This ovum is very large and it unite with the sperm to produce zygote.

There are three stages of Oogenesis, the multiplication phase, the growth phase and maturation phase.

In the multiplication phase, the germinal cells divide to form oogonia. The oogonia multiply and form oocytes. The oocytes pass through the growth phase and mature to form ovum.