Question

In monocot embryo, epicotyls has a shoot apex and few leaf primordia enclosed in a hollow foliar structure called
A. Coleorhiza
B. Epiblast
C. Scutellum
D. Coleoptile.

Answer 1

Hint: It is a pointed protective sheath covering the rising shoot in monocots.

Complete answer: Coleoptiles are cylindrical organs that ensheath the first leaf and shoot apex in grass seedlings. They assist in the emergence of the first leaf (and shoot apex) via means of saving it during its passage via the soil.
On emergence, the first leaf breaks through the coleoptile tip. Functions of Coleoptile are given below:-
It has a terminal pore for the emergence of the primary leaf.
It protects the plumule during emergence from the soil.
During germination, it performs photosynthesis.

Now lets us find the solution from given options
1. Coleorhiza is a sheath-like shape found in a monocotyledon plant seed that acts as protecting covering enclosing the radicle.
2. The epiblast is derived from the inner cell mass and lies above the hypoblast. The epiblast produced three main germ layers and to the extra embryonic mesoderm of the visceral yolk sac, the allantois, and the amnion.
3. Scutellum is the papery cotyledon of the monocot seed and acts as a passage for transfer of nutrients from the endosperm to the growing embryo.
4. Coleoptile is a foliar (leaf shaped) shaped enclosing epicotyl bearing shoot apex and leaf primordial.

Thus, the proper solution is alternative D. i.e. Coleoptile.

Note: Coleoptiles contain the very same type of cells that are all specialized to rapid stretch growth. They do not divide; however increase in size or shape as they collect more water. Coleoptiles additionally have water vessels along the axis to give a water supply.