Sex determination is the establishment of male and female individuals or male and female organs of an individual.
It can either be due to environmental, genetic or chromosomal factors.
example- In some lizards, high temperature induces maleness while low temperature induces femaleness.
example- In bacteria, fertility factor present in a plasmid determines sex.
example- In mammals, females possess two homomorphic sex chromosomes XX whereas males contain two heteromorphic sex chromosomes XY.
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