self-fertilization

self-fertilization
/self"ferr'tl euh zay"sheuhn, self'-/, n.
1. Bot. fertilization of an ovum of a plant by a male gamete from the same flower (opposed to cross-fertilization).
2. Zool. fertilization of the ovum of a hermaphroditic animal by a sperm from the same individual, as in some species of tapeworm.
[1855-60]

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Fusion of male and female sex cells (gametes) produced by the same individual.

This type of fertilization occurs in bisexual organisms, including most flowering plants, numerous protozoans, and many invertebrates. Many organisms capable of self-fertilization can also reproduce by means of cross-fertilization. As an evolutionary mechanism, self-fertilization allows an isolated individual to create a local population and stabilizes desirable genetic strains, but it fails to provide a significant degree of variability within a population and thereby limits the possibilities for adaptation to environmental change.

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      fusion of male and female gametes (sex cells) produced by the same individual. Self-fertilization occurs in bisexual organisms, including most flowering plants, numerous protozoans, and many invertebrates. Autogamy, the production of gametes by the division of a single parent cell, is frequently found in unicellular organisms such as the protozoan Paramecium. These organisms, however, may also reproduce by means of conjugation, in which cross-fertilization is achieved by the exchange of genetic material across a cytoplasmic bridge between two individuals. Likewise, among higher plants, most of which are monoecious (i.e., bisexual—male and female gametes being produced by the same individual), most self-pollinating species are also capable of cross-fertilization, and even those that are obligate self-fertilizers are occasionally cross-pollinated by accident. Hermaphroditic animals (those in which both male and female gonads are borne on one individual) are rarely capable of self-fertilization, since many such species have adaptations encouraging cross-fertilization.

      As an evolutionary and reproductive mechanism, self-fertilization allows an isolated individual to create a local population and stabilizes desirable genetic strains, but it fails to provide a significant degree of variability within a population and thereby limits the possibilities for adaptation to environmental change.

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Universalium. 2010.

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Look at other dictionaries:

  • self-fertilization — (also self fertilisation) ► NOUN Biology ▪ the fertilization of plants and some invertebrate animals by their own pollen or sperm. DERIVATIVES self fertilize verb …   English terms dictionary

  • Self-fertilization — Self fer ti*li*za tion, n. (Bot.) The fertilization of a flower by pollen from the same flower and without outer aid; autogamy. [1913 Webster] …   The Collaborative International Dictionary of English

  • self-fertilization — [self′fʉrt΄ l i zā′shən] n. fertilization of a plant or animal by its own pollen or sperm …   English World dictionary

  • self-fertilization — self fertilization. См. самооплодотворение. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • self-fertilization — self fertilization. = autogamy (см.). (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • self-fertilization — apsivaisinimas statusas T sritis ekologija ir aplinkotyra apibrėžtis Savaiminis lytinis ląstelių arba gametų susiliejimas. Yra autogaminis, dvigubasis, pasirinktinis apsivaisinimas. atitikmenys: angl. self fertilization vok. Selbstfertilität, f;… …   Ekologijos terminų aiškinamasis žodynas

  • self-fertilization — apsivaisinimas statusas T sritis augalininkystė apibrėžtis Dviejų to paties individo lytinių ląstelių savaiminis (ne dirbtinis) susiliejimas. atitikmenys: angl. autogamy; self fertilization rus. оплодотворение …   Žemės ūkio augalų selekcijos ir sėklininkystės terminų žodynas

  • self-fertilization — self′ fertiliza′tion n. dvl bot fertilization of the ovum by a male gamete of the same individual • Etymology: 1855–60 self′ fer′tilized, adj …   From formal English to slang

  • self-fertilization — Fecundation of the ovules by the pollen of the same flower, or of the ova by the spermatozoa of the same animal in hermaphrodite forms; denoting an extreme type of inbreeding seen in certain plants and animal forms which produce both male and… …   Medical dictionary

  • self-fertilization — or self fertilisation noun Biology the fertilization of plants and some invertebrate animals by their own pollen or sperm. Derivatives self fertilize verb …   English new terms dictionary

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