The phenomenon of determining the sex of an individual of a species is called sex determination.
• There are different strategies e.g., temperature, chromosomes, genes, hormones, etc. responsible for determining the sex in certain animals.
• In certain animals, the sex determination is not genetically determined. e.g., the Snails can change their sex.
• In human beings in each cell there are 22 pairs of autosomes and 1 pair of sex chromosomes. The 23rd pair is either XX as in females or XY as in males.