endosperm

American  

[en-duh-spurm] / ˈɛn dəˌspɜrm /

noun

Botany.

1. nutritive matter in seed-plant ovules, derived from the embryo sac.

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endosperm British  

/ ˈɛndəʊˌspɜːm /

noun

1. the tissue within the seed of a flowering plant that surrounds and nourishes the developing embryo

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endosperm Scientific  

/ ĕn′də-spûrm′ /

1. The tissue that surrounds and provides nourishment to the embryo in the seeds of many angiosperms. The cells of the endosperm arise from a process similar to that of fertilization. The pollen of angiosperms contains two sperm, one of which fertilizes the egg cell in the female gametophyte. The second unites with two other nuclei in the female gametophyte, producing cells that are triploid (having three sets of chromosomes) and that develop into the endosperm. In some species of angiosperms, the endosperm is absorbed by the embryo before germination, while in others it is consumed during germination. Embyros that lack an endosperm (such as peas and beans) have absorbed most of their food storage tissues before becoming dormant and develop large, fleshy cotyledons.

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Other Word Forms

• endospermic adjective

Etymology

Origin of endosperm

1840–50; < French endosperme; endo-, sperm ¹

Example Sentences

The scientists generated rice lines that express a gene that sequesters vitamin B1 in a controlled manner in the endosperm tissues.

From Science Daily • Apr. 11, 2024

Gehring’s team recently received funding to try to engineer plants that develop endosperm without being fertilized, a feat that some naturally apomictic plants are capable of.

From Science Magazine • May 17, 2023

The bran is the outer shell, the endosperm contains starch and protein, and the germ carries the genetic information of the grain and fat.

From Salon • Nov. 13, 2022

White flour is made just from the endosperm, while whole wheat contains all three parts.

From Washington Post • Oct. 15, 2021

The fruit is a capsule containing a large number of small seeds and opening by apical teeth; the seed contains a floury endosperm and a curved embryo.

From Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 4 "Carnegie Andrew" to "Casus Belli" by Various