Question

When do the oogenesis and the spermatogenesis initiate in human females and males respectively?

Answer 1

Both are the process of formation of female and male gametes. Spermatogenesis leads to the formation of sperm and oogenesis leads to the formation of ova.

Complete Answer:
- Humans reproduce sexually and are viviparous. Reproduction events in human beings include the development of gametes, i.e., sperms in males and in females an ovum, the transfer of sperms into females and the fusion of males and females to form zygotes.
- The formation and growth of blastocyst is accompanied by its attachment to the wall of the uterus, embryonic growth and delivery of the infant. These reproductive events happen after puberty. There are notable variations between male and female reproductive activities.
- Gametes that may be sperms and ovum are formed in the primary sex organs by the testis in males and ovaries in women by the process called gametogenesis.
- Spermatogenesis, which starts in puberty, produces the immature male germ cells in the testis (spermatogonia). The spermatogonia on the inside walls of seminiferous tubules multiplies and increases by mitotic division.
- Each diploid spermatogonium contains 46 chromosomes. The mechanism of forming the mature female gamete is known as oogenesis. Oogenesis is caused by several million gamete mother cells (oogonia) in each fetal ovary during the embryonic stage of development. No longer oogonia produced or additional after birth.

Note: The fetal or embryonic stage initiates oogenesis in women; in males, spermatogenesis starts in puberty. The production of sperm or spermatogenesis in men continues until age, but ovum formation in females stops with menopause at about the age of 50 years.