News tagged with males

Related topics: females , sperm

Call for circumcision gets a boost

In the United States the rate of circumcision in men has increased to 81% over the past decade. In an important new study just published in advance in Mayo Clinic Proceedings authors from Australia and the United States have s ...

Apr 02, 2014
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Midrange testosterone levels better for older men

(Medical Xpress)—Optimal levels of testosterone - meaning neither low nor high - in older men are associated with better survival, according to a study recently published by a team of UWA researchers in ...

Jan 10, 2014
popularity 5 / 5 (1) | comments 0

Male

Male (♂) refers to the sex of an organism, or part of an organism, which produces small mobile gametes, called spermatozoa. Each spermatozoon can fuse with a larger female gamete or ovum, in the process of fertilization. A male cannot reproduce sexually without access to at least one ovum from a female, but some organisms can reproduce both sexually and asexually.

Not all species share a common sex-determination system. In humans and most animals, sex is determined genetically but in other species it can be determined due to social, environmental, or other factors. The existence of two sexes seems to have been selected independently across different evolutionary lineages (see Convergent Evolution). Accordingly, sex is defined operationally across species by the type of gametes produced (ie: spermatozoa vs. ova) and differences between males and females in one lineage are not always predictive of differences in another.

Male/Female dimorphism between organisms or reproductive organs of different sexes is not limited to animals; male gametes are produced by chytrids, diatoms and land plants, among others. In land plants, female and male designate not only the female and male gamete-producing organisms and structures but also the structures of the sporophytes that give rise to male and female plants.

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