Gametophyte
Translation- Gametophyte
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Several gametophytes growing in a terrarium.
A gametophyte is the haploid, multicellular phase of plants and algae that undergo alternation of generations, with each of its cells containing only a single set of chromosomes.
The gametophyte produces male or female gametes (or both), by a process of cell division called mitosis. The fusion of male and female gametes produces a diploid zygote, which develops by repeated mitotic cell divisions into a multicellular sporophyte. Because the sporophyte is the product of the fusion of two haploid gametes, its cells are diploid, containing two sets of chromosomes. The mature sporophyte produces spores by a process called meiosis, sometimes referred to as "reduction division" because the chromosome pairs are separated once again to form single sets. The spores are therefore once again haploid and develop into a haploid gametophyte.
In mosses, liverworts and hornworts (bryophytes), the gametophyte is the commonly known phase of the plant. An early developmental stage in the gametophyte of mosses (immediately following germination of the meiospore) is called the protonema. The adult gametophyte of mosses is called the gametophore as it carries the gamete-producing sex organs. [1]
In most other land plants, the gametophyte is very small. In ferns the gametophyte is a free living organism called the prothallus, in contrast to angiosperms.[2]
In gymnosperms and angiosperms, the gametophyte are reduced to only a few cells; in angiosperms the female gametophyte (sometimes called the "embryo sac") is known as a megagametophyte and the male gametophyte (pollen) is called a microgametophyte.
In some multicellular green algae, red algae, or brown algae (Ulva is one example), the sporophytes and gametophytes are often isomorphic, but in some species the gametophyte may be reduced.
References
- ^ Ralf Reski(1998): Development, genetics and molecular biology of mosses. In: Botanica Acta 111, pp 1-15.
- ^ C.Michael Hogan. 2010. Fern. Encyclopedia of Earth. National council for Science and the Environment. Washington, DC
See also
Botany Subdisciplines of botany Ethnobotany · Paleobotany · Plant anatomy · Plant ecology · Plant evo-devo · Plant morphology · Plant physiology
Plants Plant parts Plant cells Plant reproduction Alternation of generations · Gametophyte · Plant sexuality · Pollen · Pollination · Seed · Spore · SporophytePlant taxonomy Glossaries Category · Portal Categories:- Plant morphology
- Plant anatomy
- Plant reproduction
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Gametophyte — Ga*me to*phyte, n. [Gamete + Gr. fyto n plant.] (Bot.) In the alternation of generations in plants, that generation or phase which bears sex organs and produces gametes. In the lower plants, as the alg[ae], the gametophyte is the conspicuous part … The Collaborative International Dictionary of English
gametophyte — 1> биол. гаметофит … Новый большой англо-русский словарь
gametophyte — gametophyte. См. гаметофит. (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.
gametophyte — gametophytic /geuh mee teuh fit ik, gam i /, adj. /geuh mee teuh fuyt , gam i /, n. Bot. the sexual form of a plant in the alternation of generations. Cf. sporophyte. [1890 95; GAMETO + PHYTE] * * * In certain plants, the sexual phase (or an… … Universalium
gametophyte — (биология) гаметофит … Большой англо-русский и русско-английский словарь
gametophyte — noun Etymology: International Scientific Vocabulary Date: circa 1889 the haploid generation of a plant or fungus with alternation of generations that begins with haploid spore or gamete producing bodies and ends with fertilization producing a… … New Collegiate Dictionary
Gametophyte — Gamétophyte Cet article est une ébauche concernant la botanique. Vous pouvez partager vos connaissances en l’améliorant (comment ?) selon les recommandations des projets correspondants … Wikipédia en Français
gametophyte — Haploid stage of life cycle of plants; the major vegetative stage for simple plants like liverworts … Dictionary of molecular biology
gametophyte — noun The plant (or the haploid phase in its life cycle) which produces gametes by mitosis in order to produce a zygote. See Also: gametangium, gamete, gametogenesis, gametophytic … Wiktionary
gametophyte — гаметофит Гаплоидное, образующее гаметы поколение в жизненном цикле растений, характеризующихся чередованием поколений alternation of generations; гаметы продуцируются в специализированных гаметангиях либо в любом участке таллома (у некоторых… … Англо-русский толковый словарь генетических терминов
