Diseases, Conditions, Syndromes

Buzz off: breakthrough technique eradicates mosquitoes

A breakthrough technique harnessing two methods to target disease-carrying mosquitoes was able to effectively eradicate buzzing biters in two test sites in China, according to research published on Thursday.

Psychology & Psychiatry

Reproductive hormones related to how attractive a woman smells

Reproductive hormones control a woman's monthly cycle and regulate fertility. Reproductive hormones are also related to how attractive a woman smells a study now shows. Researchers at the University of Bern demonstrate that ...

Health

Studies offer no clear answers on safety of cellphone use

Two government studies that bombarded rats and mice with cellphone radiation found a weak link to some heart tumors, but scientists and federal regulators say don't worry—it is still safe to use your device.

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Female

Female (♀) is the sex of an organism, or a part of an organism, which produces mobile ova (egg cells). The ova are defined as the larger gametes in a heterogamous reproduction system, while the smaller, usually motile gamete, the spermatozoon, is produced by the male. A female individual cannot reproduce sexually without access to the gametes of a male (an exception is parthenogenesis). Some organisms can reproduce both sexually and asexually.

There is no single genetic mechanism behind sex differences in different species and the existence of two sexes seems to have evolved multiple times independently in different evolutionary lineages. Other than the defining difference in the type of gamete produced, differences between males and females in one lineage cannot always be predicted by differences in another. The concept is not limited to animals; egg cells are produced by chytrids, diatoms, water moulds and land plants, among others. In land plants, female and male designate not only the egg- and sperm-producing organisms and structures, but also the structures of the sporophytes that give rise to male and female plants.

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