Gametogenesissex cell beginning

Gametogenesis – gamete formation where daughter cells, or gametes, are produced at the end of meiosis II resulting in the production of sperm and egg.

2 Types of Gamete FormationSpermatogenesis – the

process of male gamete production in animals

Oogenesis – the process of female gamete production in animals

Spermatogenesis pictures

Spermatogenesis process•Spermatogenesis begins with diploid germ cells called spermatogonia that grow and develop into a primary spermatocyte.

•During meiosis I, one spermatigonium divides into two cells called secondary spermatocytes.

•Secondary spermatocytes undergo meiosis II to form spermatids, which develop into sperm.

•In the end, from 1 parent spermatigonium 4 sperm cells are produced.

Spermatogenesis notes•Spermatogenesis occurs inside testes•Within testes spermatogenesis occurs in walls of seminiferous tubules •Mature sperm are released into lumen of seminiferous tubules. •Spermatigonia & Primary spermatocytes are 2n•Secondary spermatocytes are 1n•Spermatids and sperm are 1n

Oogenesis pictures

Oogenesis process•Oogenesis begins with a diploid cell called an oogonium. •After growth and development, one oogonium forms one primary oocyte.•Meiosis I produces a secondary oocyte and one polar body (due to unequal division of the cytoplasm). •Meiosis II in the secondary oocyte produces an egg and polar body. Meiosis II in first polar body produces 2 polar bodies.•The egg survives, while all the polar bodies die. •Only one functional egg cell comes from this process, as the unequal division of the cytoplasm makes the egg cell big (needs extra nutrients).

Oogenesis notes•Oogenesis occurs inside the ovary•Within testes oogenesis occurs in a follicle •Eggs are released into oviduct•Oogonium & Primary oocytes are 2n•Secondary oocytes are 1n•Polar bodies and eggs are 1n

Oogenesis vs. Spermatogenesis

oogenesis spermatogenesis

Gametes produces 1 4

Location Ovary Testes