Information AboutFemale |
|
Female is the Sex of an Organism , or a part of an organism, which produces Ova (egg cells). The ova are defined as the larger Gamete s in a Heterogamous reproduction system, while the smaller, usually Motile gamete, the Spermatozoon is produced by the Male . A female individual cannot reproduce Sexually without access to the gametes of a Male . Some organisms can reproduce both Sexually and Asexually . There is no single genetic mechanism behind sex differences in different species, and the existence of two sexes seems to have Evolved multiple times independently in different Evolutionary Lineages . Other than the defining difference in the type of gamete produced, differences between males and females in one lineage cannot always be predicted by differences in another. The concept is not limited to Animal s; egg cells are produced by Chytrid s, Diatom s, Water Mold s, and Land Plants , among others. In land plants, 'female' and 'male' designate not only the egg- and sperm-producing organisms and structures, but also the structures of the Sporophyte s that give rise to male and female plants. SEX DETERMINATION See Also: Sex-determination system The sex of a particular organism may be determined by a number of factors. These may be genetic or environmental, or may naturally change during the course of an organism's life. Although most species with male and female sexes have individuals that are either male or female, Hermaphroditic animals have both male and female reproductive organs. Genetic determination Most Mammal s, including Human s, are genetically determined as such by the XY Sex-determination System where males have an XY (as opposed to XX) sex Chromosome . During Reproduction , a male can give either an X sperm or a Y sperm, while a female can only give an X egg. A Y sperm and an X egg produce a Boy , while an X sperm and an X egg produce a Girl . The ZW Sex-determination System , where males have a ZZ (as opposed to ZW) sex chromosome may be found in Bird s and some Insect s and other organisms. Members of Hymenoptera , such as Ant s and Bee s, are determined by Haplodiploidy , where most males are Haploid and females and some sterile males are Diploid . Environmental determination In some species of reptiles, including , the dominant individual in a group becomes female while the other ones are male. In some Arthropod s, sex is determined by infection. Bacteria of the genus '' Wolbachia '' alter their sex; some species consist entirely of ZZ individuals, with sex determined by the presence of ''Wolbachia''. MAMMALIAN FEMALE The mammalian female is characterised by having two copies of the X chromosome as opposed to the male which carries only one X and one smaller Y chromosome. To compensate for the difference in size one of the female's X chromosomes is randomly inactivated in each cell. Conversely in birds it is the female who is heterozygote and carries a Z and a W chromosome whilst the male carries two Z chromosomes. Human female In humans, there are several different components (in addition to genetics) to both biological Sex and Gender identity by which people assign the label "female". SYMBOLS A common symbol used to represent the female gender is ♀ ( and is a stylized representation of the Goddess Venus' hand mirror. SEE ALSO
|
|
|