The female ( female ) - in biological species that have sexual reproduction and associated sexual dimorphism , a form of a living organism that has female sexual characteristics of its own species and differs from the male form ( male ) of the same biological species. The number of female genital traits include primary (the presence of not the male, but the female reproductive system (female genital organs)), secondary (especially the physique, etc.) and others. Female and male specimens are distinguished in animals and plants, but the terms "female" and "male" are used in relation to animals.
Content
Key Features
The main characteristic of the female is its ability to produce female gametes - eggs , differing in their larger size and lower mobility, unlike spermatozoa produced by males , and the ability to reproduce offspring (as a rule, only in the presence of genetic material obtained from the male, but in nature found parthenogenesis - the ability to reproduce without the participation of the male). The female sex is considered more ancient than the male, since at an early stage of evolution, all populations of organisms had the ability to reproduce offspring and were called isogamic organisms ; All animals of the highest kingdom, including man, belong to oogamic organisms [1] .
Most of the females of arthropods and chordates lay eggs , rarely they have live birth , typical, however, for the entire class of mammals included in the type of chordates. Mammalian females are characterized by the presence of mammary glands , with the help of which the female feeds her baby milk . Males also have mammary glands, but in a rudimentary form and they do not perform their function. Mammalian females, especially among social species, often have smaller sizes and less pronounced musculature . Among birds, gender differences can be seen in the coloration of the female; they often have a more modest coloration in contrast to the bright plumage of the male.
A characteristic feature of the female mammal is the presence of a chromosomal pair XX, while in the male it is XY. In birds, sex is determined by the sex chromosomes Z and W; ZZ is male, and ZW is female, so the sex of the chick is determined by the maternal gene, in contrast to mammals and humans.
Female Biological Role
The biological role of females in the population is extremely diverse. Depending on the type of living organism, the role of the female may include: protecting the representatives of their own species, protecting the territory, managing the group, obtaining resources, raising children, and much more. Among other things, one of the main roles of the female within its species is the performance of the reproductive function β that is, the reception of genetic information contained in the germ cells ( spermatozoa ) of the male sex cells of the female (for example, eggs ).
See also
- Woman
- Intersex
- Hermaphroditism
Notes
- β Dusenbery, David B. (2009). Living at Micro Scale , Chapter 20. Harvard University Press, Cambridge, Mass. ISBN 978-0-674-03116-6 .
Literature
- Ayers, Donald M. English Words from Latin and Greek Elements . Second Edition. 1986. University of Arizona Press. United States.