Health

Secondary students' sexual health survey

Sexually active Australian secondary students tend to engage in responsible sexual behaviour but there is still room to improve knowledge and education for this group, according to a nationwide survey conducted by La Trobe ...

Medical research

First clinical guidance on anal sex after prostate cancer

UK doctors and surgeons have formulated what is probably the world's first clinical guidance on anal sex before, during, and after diagnosis and treatment for prostate cancer. This consensus guideline, which is aimed at clinicians ...

Health

The lifelong health benefits of intimacy

(HealthDay)—Much research has explored the mental and physical health benefits of maintaining social contacts well into later life. Studies also show that maintaining sexual health can have profound benefits that may include ...

Psychology & Psychiatry

Passion trumps love for sex in relationships

Men initiate sex more than three times as often as women do in a long-term, heterosexual relationship. However, previous research shows that sex happens far more often whenever the woman takes the initiative, suggesting that ...

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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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