polar nucleus

polar nucleus
Bot. either of two female haploid nuclei, in the embryo sac of flowers, that fuse to produce a diploid nucleus, which combines with a male nucleus to form the endosperm.
[1880-85]

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Universalium. 2010.

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  • polar nucleus — noun : either of two nuclei that fuse in the center of the embryo sac of a seed plant to form the primary endosperm nucleus * * * Bot. either of two female haploid nuclei, in the embryo sac of flowers, that fuse to produce a diploid nucleus,… …   Useful english dictionary

  • polar nucleus — po′lar nu′cleus n. bot either of two female haploid nuclei, in the embryo sac of flowers, that fuse to produce a diploid nucleus • Etymology: 1880–85 …   From formal English to slang

  • polar nucleus — noun Date: 1882 either of the two nuclei of a seed plant embryo sac that are destined to form endosperm …   New Collegiate Dictionary

  • polar body — n a cell that separates from an oocyte during meiosis: a) one containing a nucleus produced in the first meiotic division called also first polar body b) one containing a nucleus produced in the second meiotic division called also second polar… …   Medical dictionary

  • polar fusion nucleus — polar fusion nucleus. См. вторичное ядро. (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.

  • polar bodies — 1. small nonfunctional cells with a haploid chromosome complement, consisting of a small amount of cytoplasm and a nucleus, resulting from unequal division of the primary oocyte (first polar b.) and, if fertilization occurs, of the secondary… …   Medical dictionary

  • polar body — In animals each meiotic division of the oocyte leads to the formation of one large cell (the egg) and a small polar body as the other cell. Polar body formation is a consequence of the very eccentric position of the nucleus and the spindle …   Dictionary of molecular biology

  • polar body — noun Date: 1888 a cell that separates from an oocyte during meiosis and that contains a nucleus produced in the first or second meiotic division and very little cytoplasm …   New Collegiate Dictionary

  • endosperm nucleus — noun Date: circa 1902 the triploid nucleus formed in the embryo sac of a seed plant by fusion of a sperm nucleus with two polar nuclei or with a nucleus formed by the prior fusion of the polar nuclei …   New Collegiate Dictionary

  • endosperm nucleus — noun : the triploid nucleus formed in the embryo sac of a seed plant by fusion of a sperm nucleus with the two polar nuclei or with a nucleus produced by their prior fusion compare double fertilization …   Useful english dictionary

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