Question

In L.S. embryo of grass, which one shows the correct labelling.

• A. a—root cap, b—shoot apex, c—scutellum, d—coleoptile, e—epiblast, f—radicle, g—coleorhiza
• B. a—scutellum, b—coleoptile, c—shoot apex, d— epiblast, e—radicle, f—root cap, g—coleorhiza
• C. a—coleoptile, b—scutellum, c—radicle, d—shoot apex, e—epiblast, f—coleorhiza, g—root cap
• D. a—coleorhiza, b—radicle, c—epiblast, d—coleoptile, e—root cap, f—scutellum, g—shoot apex

Answer 1

The correct option is B a—scutellum, b—coleoptile, c—shoot apex, d— epiblast, e—radicle, f—root cap, g—coleorhiza

Scutellum
The monocot embryo shows the presence of a single cotyledon called scutellum which is present on the lateral side of the embryonal axis. Hence, the part labelled ‘a’ is scutellum.

The plumule is protected by a sheath called coleoptile which is represented by ‘b’.

The terminal end of the epicotyl has the shoot apex represented by ‘c’.

Epiblast of the monocot embryo is the residue of the second cotyledon which does not develop in monocots. It lies on the side of the embryonal axis. It is represented by the part labelled ‘d’.

The lower end of the embryonal axis consists of the radicle or root tip which gives rise to the root system. It is represented by ‘e’.


The root cap is the sheath covering the root tip. It is represented by ‘f’ in the embryonic stage.

The lower end of the embryonal axis consists of the radicle or root tip and root cap which are covered by a protective sheath called coleorhiza. It is represented by ‘g’ in the given image.


Final answer
(a) a—scutellum, b—coleoptile, c—shoot apex, d— epiblast, e—radicle, f—root cap, g—coleorhiza