Test: The Seed (NCERT) - NEET MCQ

The single cotyledon of monocotyledonous seed (e.g., maize grain) is called scutellum. It occupies the major portion of the embryo regions of grains.

The embryonal axis is differentiated into radicle and plumule. In monocot seeds, the radicle is protected by a sheath called coleorhiza and the plumule is protected by coleoptile whereas in dicot seeds, the radicle and plumule are not protected by such sheaths.

Food storing tissue of a seed is endosperm. In flowering plants it is produced as a result of double fertilization. In most monocots and some dicot seeds, the food reserve remains in the endosperm. They are called endospermic or albuminous seeds, example: cereals, castor bean, coconuts, rubber. In majority of dicot seeds (example: pea, gram, bean, mustard, groundnut) and some monocot seeds (example: orchids, Sagittaria), the endosperm is consumed during seed development and the food is stored in cotyledons and other regions. They are called non-endospermic or exalbuminous seeds.

In the section of Maize seed we observe:
(A) The nutritive layer - the endosperm
(B) The protective covering of the plumule- the coleoptile
(C) The root forming structure  -the radicle, protected by coleorhiza
(D) The nutritive protein layer- the aleurone

Monocotyledonous seeds are with a single cotyledon. The fruit wall (pericarp) and the seed coat (testa) are inseparably fused. Below the grain covering are present two structures, endosperm and embryo. The embryo in the pointed part of the grain, mostly towards the upper side. It consists of an embryo axis containing a radicle plumule and a single lateral cotyledon. The radicle for sheaths, inner root cap and outer coleorhiza. The (or future shoot) goes towards the reader side of the given at the other end of embryo axis. It bears a few rudimentary leaves and a conical protective sheath called coleoptile. The single cotyledon of monocotyledonous seed is called scutellum. It occupies the major embryo regions of grain. The endosperm occupies of the interior of the grain on the broader sides.