Organisms of many
species are specialized into
male and
female varieties, each known as a
sex.
Sexual reproduction involves the combining and mixing of
genetic traits: specialized
cells known as
gametes combine to form offspring that inherit traits from each parent. Gametes can be identical in form and function (known as
isogamy), but in many cases an asymmetry has evolved such that two sex-specific types of gametes (heterogametes) exist (known as
anisogamy).