Question

Monocot root has

• A. Conjoint, collateral, open, polyarch vascular bundles
• B. Suberized exodermis, casparian strip, passage cells, cambium
• C. Suberized exodermis, polyarch xylem, exarch xylem and pith
• D. Exodermis, endarch, tetrach vascular bundles

Answer 1

The correct option is C Suberized exodermis, polyarch xylem, exarch xylem and pith

Vascular bundles of monocot root are radial in arrangement. There are eight bundles each of xylem and phloem. Hence, the condition is described as polyarch.

Xylem is described as exarch in them. Pith is the innermost region of the root, representing the central axis. It is composed of few loosely arranged parenchyma cells. In monocot roots, just under the epidermis forming the outermost layer of the cortex is a layer one or two cells in width called as the hypodermis. Since its cell walls are heavily suberized and impermeable to water its apparent function is to keep the water and nutrients, which are absorbed in the root zone further down the root from leaking out through the cortex. Thus, option C is correct.