Life Science: Session 3 Sex Cell Production What are sex cells?
Sex cells, or gametes, are unique to organisms that reproduce
sexually. In animals and plants (fungi are somewhat different in
this regard) there are two types of sex cells: male and female.
The male sex cells are sperm, while the female sex cells are
eggs. Sex cells are formed from special body cells that are
typically located in sex organs. In most animals, sperm are
formed in the testes of males, and eggs are formed in the
ovaries of females. Sex cells contain only half of the
hereditary material present in the body cells that form them.
This is important because male and female sex cells ultimately
join to become a fertilized egg, which gives rise to a new
organism, or offspring. In order for the offspring to resemble
its parents, its first cell must receive the entire genome from
its two parents. For humans, we know there are 46 chromosomes in
body cells existing as 23 pairs. A fertilized egg must therefore
contain this same number and arran