See also: Evolution of sexual reproduction and Sex § Evolution of sex 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. 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. ova) and differences between males and females in one lineage are not always predictive of differences in another. Īccordingly, sex is defined across species by the type of gametes produced (i.e.: spermatozoa vs. There is a good argument that this pattern was driven by the physical constraints on the mechanisms by which two gametes get together as required for sexual reproduction. The repeated pattern is sexual reproduction in isogamous species with two or more mating types with gametes of identical form and behavior (but different at the molecular level) to anisogamous species with gametes of male and female types to oogamous species in which the female gamete is very much larger than the male and has no ability to move.
The existence of separate sexes has evolved independently at different times and in different lineages (see convergent evolution). In humans, the word male can also be used to refer to gender. In most animals, including humans, sex is determined genetically however, species such as Cymothoa exigua change sex depending on the number of females present in the vicinity. Not all species share a common sex-determination system. Most male mammals, including male humans, have a Y chromosome, which codes for the production of larger amounts of testosterone to develop male reproductive organs. Male (symbol: ♂) is the sex of an organism that produces the gamete (sex cell) known as sperm, which fuses with the larger female gamete, or ovum, in the process of fertilization.Ī male organism cannot reproduce sexually without access to at least one ovum from a female, but some organisms can reproduce both sexually and asexually. It also stands for the planet Mars and is the alchemical symbol for iron. The symbol of the Roman god Mars (god of war) is often used to represent the male sex.
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