News tagged with males

Related topics: females · sperm

CDC: stillbirths now outnumber infant deaths in U.S.

(HealthDay)—Stillbirths have eclipsed infant deaths for the first time in the United States, according to new research published in the U.S. Centers for Disease Control and Prevention's July 23 National Vital Statistics ...

Jul 24, 2015
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Illicit drug use may affect sexual function in men

In a study of 1159 males who illicitly used amphetamines, half of participants said drug use had no impact on their sexual functions, while the other half reported impacts such as reduced erectile rigidity and sexual satisfaction, ...

Jul 06, 2015
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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.

This text uses material from Wikipedia, licensed under CC BY-SA

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