News tagged with males

Related topics: females , sperm

Firearm violence trends in the 21st century

While the overall death rate from firearm violence has remained unchanged for more than a decade, the patterns for suicide and homicide have changed dramatically, a UC Davis study on the epidemiology of gun ...

Dec 17, 2014
popularity 4.4 / 5 (12) | comments 1

Male and female breast cancers are not identical

Results of the EORTC10085/TBCRC/BIG/NABCG International Male Breast Cancer Program conducted in both Europe and in the United States and presented at the 2014 San Antonio Breast Cancer Symposium found significant improvement ...

Dec 12, 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.

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