What is Endosperm?
[[File:Wheat-kernel_nutrition.png|thumb|250px|alt=Diagram showing how much of a kernel is made up of endosperm (83%) and where it is (in the centre)|What is in a [[wheat]] kenel]] '''Endosperm''' is a food reserve [[tissue]] inside the [[seed]]s of most [[flowering plant]]s. It surrounds the [[embryo]] and provides nutrition in the form of [[starch]]. It may also have [[Vegetable oil|oil]]s and [[protein]]. The endosperm of [[cereal]] plants can be a source of energy for humans. [[Wheat]] endosperm is ground into [[flour]] for [[bread]]. With whole wheat bread the [[bran]] (cover of seed) and the [[Cereal germ|germ]] is also in the flour. [[Barley]] endosperm is the main source for [[beer]] production. Other examples of edible endosperms are [[coconut]] 'meat' and coconut 'water',<ref>{{cite web |url=http://waynesword.palomar.edu/ecoph10.htm |url-status=dead |archive-url=https://web.archive.org/web/20170902214354/http://waynesword.palomar.edu/ecoph10.htm |archive-date=2 September 2017 |title=Edible Palm Fruits |last=Armstrong |first=W. P. |website=Palomar College |access-date=8 June 2012 }}</ref> and [[Maize|corn]], including [[popcorn]]. Some plants, like the [[orchid]]s, lack endosperm in their [[seed]]s. ==Origin of endosperm== Primitive ([[basal]]) flowering plants have seeds with small [[embryo]]s and big endosperms. The [[evolution]]ary development of flowering plants tends to show a trend towards plants with seeds with little or no endosperm. In more [[derived]] flowering plants the embryo occupies most of the seed and the endosperm is not developed or consumed before the seed matures. In these plants, the [[cotyledon]]s contain the food reserve.<ref>{{cite web|url=http://www.seedbiology.de/dormancy.asp#evolution|title=The Seed Biology Place - Seed Dormancy|website=www.seedbiology.de}}</ref><ref name=Friedman1998>{{citation | author = Friedman, William E. | year = 1998 | title = The evolution of double fertilization and endosperm: an historical perspective | journal = Sexual Plant Reproduction | volume