The wheat grain has an embryo with one large, shield shaped cotyledon known as

Large shield-shaped cotyledon of wheat grain is called scutellum. Wheat is a cereal and grass.
(2) The membranous, hollow covering, with apical opening present around the plumule of monocot embryo, is called coleoptile. 
(3) Epiblast is lateral outgrowth of coleorhiza of grass embryo. 
(4) Coleorhiza is membranous covering present around the radicle of monocot embryo.