Biological sex

Trait that determines an organism's sexually reproductive function

Sex is the phenotypic trait of a sexually reproducing organism in producing gametes of one of two different sizes or shapes—male or female gametes. During sexual reproduction, a male and a female gamete fuse to form a zygote, which develops into an offspring that inherits traits from each parent. By convention, organisms that produce smaller gametes (spermatozoa, sperm) are called male, while organisms that produce larger gametes (ova, often called egg cells) are called female.

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