cross-fertilization

cross-fertilization
/kraws"ferr'tl euh zay"sheuhn, kros"-/, n.
1. Biol. the fertilization of an organism by the fusion of an egg from one individual with a sperm or male gamete from a different individual.
2. Bot. fertilization of the flower of one plant by a gamete from the flower of a closely related plant (opposed to self-fertilization).
3. (not in technical use) cross-pollination.
4. interaction or interchange, as between two or more cultures, fields of activity or knowledge, or the like, that is mutually beneficial and productive: a cross-fertilization of scientific and technical disciplines.
[1875-80]

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Fusion of male and female sex cells from different individuals of the same species.

Cross-fertilization is necessary in animal and plant species that have male and female organs on separate individuals. Methods of cross-fertilization are diverse in animals. Among most species that breed in water, the males and females shed their sex cells into the water, where fertilization takes place outside the body. Among land breeders, fertilization is internal, with the sperm being introduced into the body of the female. By recombining genetic material from two parents, cross-fertilization maintains a greater range of variability for natural selection to act on, thereby increasing the capacity of a species to adapt to environmental change. See also self-fertilization.

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also called  Allogamy,  

      the fusion of male and female gametes (gamete) (sex cells) from different individuals of the same species. Cross-fertilization must occur in dioecious plants (those having male and female organs on separate individuals) and in all animal species in which there are separate male and female individuals. Even among hermaphrodites—i.e., those organisms in which the same individual produces both sperm and eggs—many species possess well-developed mechanisms that ensure cross-fertilization. Moreover, many of the hermaphroditic species that are capable of self-fertilization (q.v.) also have capabilities for cross-fertilization.

      There are a number of ways in which the sex cells of two separate individuals can be brought together. In lower plants, such as mosses and liverworts, motile sperm are released from one individual and swim through a film of moisture to the egg-bearing structure of another individual. In higher plants, cross-fertilization is achieved via cross-pollination, when pollen grains (which give rise to sperm) are transferred from the cones or flowers of one plant to egg-bearing cones or flowers of another. Cross-pollination may occur by wind, as in conifers, or via symbiotic relationships with various animals (e.g., bees and certain birds and bats) that carry pollen from plant to plant while feeding on nectar.

      Methods of cross-fertilization are equally diverse in animals. Among most species that breed in aquatic habitats, the males and females each shed their sex cells into the water and external fertilization takes place. Among terrestrial breeders, however, fertilization is internal, with the sperm being introduced into the body of the female. Internal fertilization also occurs among some fishes and other aquatic breeders.

      By recombining genetic material from two parents, cross-fertilization helps maintain a greater range of variability for natural selection to act upon, thereby increasing a species's capacity to adapt to environmental change.

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Universalium. 2010.

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Look at other dictionaries:

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  • Cross fertilization — Fertilization Fer ti*li*za tion, n. 1. The act or process of rendering fertile. [1913 Webster] 2. (Biol.) The act of fecundating or impregnating animal or vegetable germs; esp., the process by which in flowers the pollen renders the ovule fertile …   The Collaborative International Dictionary of English

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  • Cross-fertilization — can refer to: Allogamy, where an ovum from one individual is fertilized with the spermatozoa of another Heterosis, where different strains are cross bred to form a hybrid the union of pollen from the anther of the stamen, with the female gametes… …   Wikipedia

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  • cross-fertilization — noun 1. fertilization by the union of male and female gametes from different individual of the same species • Syn: ↑cross fertilisation • Ant: ↑self fertilization • Derivationally related forms: ↑cross fertilise (for: ↑ …   Useful english dictionary

  • cross-fertilization — UK / US noun [countable/uncountable] Word forms cross fertilization : singular cross fertilization plural cross fertilizations 1) biology the process of fertilizing one type of plant with pollen from a different type of plant in order to produce… …   English dictionary

  • cross-fertilization —  Mixing of ideas.  ► “Collaborative R&D* provides a forum for technical exchange and the cross fertilization of ideas among member companies.” (Mechanical Engineering, Sept. 1994, p. 85) …   American business jargon

  • cross-fertilization — cross′ fertiliza′tion n. 1) gen the fertilization of an organism by the fusion of an egg from one individual with a sperm or male gamete from a different individual 2) bot the fertilization of the flower of one plant by a gamete from the flower… …   From formal English to slang

  • cross-fertilization — cross fer·til·iza·tion or Brit cross fer·til·isa·tion .fərt əl ə zā shən n fertilization in which the gametes are produced by separate individuals or sometimes by individuals of different kinds …   Medical dictionary

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