Diseases, Conditions, Syndromes

Taste, smell dysfunction with COVID-19 can be severe

(HealthDay)—COVID-19 should be suspected when patients present with a severe reduction of taste and smell in the absence of severe nasal obstruction, according to a study published online June 18 in JAMA Otolaryngology-Head ...

Diseases, Conditions, Syndromes

Brazil during the 1918 flu epidemic

While the impact of the 1918 Spanish flu on the developed world has been extensively researched, a lot less is known about its health effects on the Global South.

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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.

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