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Related to Endosperm: endosperm nucleus


The nutritive protein material within the embryo sac of seed plants.
Storage tissue in the seeds of gymnosperms.



in the seed of gymnosperms and most flowering plants, a tissue in which the nutrient substances necessary for the development of the embryo are deposited. In gymnosperms the endosperm is formed in the ovule during germination of the megaspore; it consequently becomes the female prothallus (gametophyte), with a haploid set of chromosomes. The archegonia in gynosperms develop from certain cells of the endosperm. In angiosperms the endosperm is formed after fertilization as a result of the merging of the spermatozoid with the secondary (diploid) nucleus of the embryo sac. In this case the cells of the endosperm are triploid. By uniting sets of chromosomes from both parent plants the endosperm becomes a physiologically active, viable nutrient tissue. It not only feeds the embryo but fosters embryonic growth and differentiation.

A distinction may be made between the nuclear, cellular, and helobial types of endosperm. In the first type the cell walls do not form immediately after formation of the nuclei. In cellular endosperms the cell walls form immediately after each division of the nuclei. Helobial endosperm is intermediate between the other two types. Endosperm is not equally developed in the mature seeds of flowering plants of different families. Thus, it is large in Gramineae, Solanaceae, and Umbelliferae, but in many other families, for example, Leguminosae, Compositae, and Rosaceae, the endosperm is poorly developed, and reserve nutrient matter is deposited in the embryo itself, mainly in the cotyledons. In many Orchidaceae the endosperm is not formed.


Khudiak, M. I. Endosperm pokrytosemennykh rastenii. Kiev, 1963.
Poddubnaia-Arnol’di, V. A. Tsitoembriologiia pokrytosemennykh rastenii. Moscow, 1976.
References in periodicals archive ?
Endosperm balance number can be reduced through anther culture or
The importance of Endosperm Balance Number in potato breeding and the evolution of tuber-bearing Solanum species.
The main chain polymer of guar endosperm polysaccharide is composed of mannose.
The youngsters have their dad's cone size, pollen size, and flattened arrays of twigs, as well as pollen and endosperm with a double set of chromosomes.
Additionally, all seeds of Ceroxyloideae have a homogenous endosperm (Dransfield et al.
There is evidence that the endosperm structure of cereals may also affect their nutritive quality.
After the endosperm was finely milled, the starch and gluten particles were separated from the pericarp and other large kernel fragments by sieving the slurry through 0.
Endemic to Central Africa, adult female CBB bore into developing berries, where they oviposit and the resultant larvae develop on the endosperm, reducing both yield and quality of the marketable product (Le Pelley 1968; Baker 1999; Vega et al.
When grains like wheat are refined to create white flour, the protective outer layer and the inner layer are discarded, leaving just the middle part, known as endosperm, which contains protein and carbohydrates.
Sabinsa's process extracts green coconut water, a liquid endosperm of maturing coconut, at optimal maturity when high levels of RNA (ribonucleic acid), critical for amino acid transport and respiratory metabolism of living cells, are present.
On the other hand, white bread is produced by separating the germ and husk from the endosperm that is ground to make white flour, thus depriving white bread of all nutrients present in the whole wheat grain making it a much poorer option.