embryo sac


nounBotany.
  1. the megaspore of a seed-bearing plant, situated within the ovule, giving rise to the endosperm and forming the egg cell or nucleus from which the embryo plant develops after fertilization.

Origin of embryo sac

1
First recorded in 1870–75

Words Nearby embryo sac

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use embryo sac in a sentence

British Dictionary definitions for embryo sac

embryo sac

noun
  1. the structure within a plant ovule that contains the egg cell: develops from the megaspore and contains the embryo plant and endosperm after fertilization

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for embryo sac

embryo sac

  1. An oval structure within an ovule of an angiosperm that contains the egg. Together with the fertilized egg, it develops into a seed. The embryo sac is the female gametophyte of angiosperms, consisting of eight nuclei: the egg and two adjacent and short-lived synergids that are near the micropyle (the opening where the pollen nuclei will enter), two central nuclei (which will combine with one of the pollen nuclei to form the endosperm), and three antipodal nuclei at the end of the embryo sac opposite the micropyle. Like the synergids, these nuclei degenerate at or shortly after fertilization. See more at gametophyte pollination.

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