Related topics: men

Male size advantage drives evolution of sex change in reef fish

Some species of fish, notably parrotfish and wrasses living on coral reefs, change their biological sex as they age, beginning life as females and later becoming functionally male. New work from the University of California, ...

Romosexuality: Embracing queer sex and love in Ancient times

Greek homosexuality has been set upon a pedestal, deemed a worthy and respectable model for romance by philosophers, writers and lovers alike. The reality is, though, that love and sex for the queer community owe more to ...

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Sex

In biology, sex is a process of combining and mixing genetic traits, often resulting in the specialization of organisms into male and female types (or sexes). Sexual reproduction involves combining specialized cells (gametes) to form offspring that inherit traits from both parents. Gametes can be identical in form and function (known as isogametes), but in many cases an asymmetry has evolved such that two sex-specific types of gametes (heterogametes) exist: male gametes are small, motile, and optimized to transport their genetic information over a distance, while female gametes are large, non-motile and contain the nutrients necessary for the early development of the young organism.

An organism's sex is defined by the gametes it produces: males produce male gametes (spermatozoa, or sperm) while females produce female gametes (ova, or egg cells); individual organisms which produce both male and female gametes are termed hermaphroditic. Frequently, physical differences are associated with the different sexes of an organism; these sexual dimorphisms can reflect the different reproductive pressures the sexes experience.

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