1. Root is the descending portion of the axis of the embryo and grows away from light. It is nongreen in colour. Exceptional cases are seen in the aerial roots of Tinospora, the root of which is green when exposed to light for a prolonged period. In Some epiphytic orchids and submerged roots (e.g., Trapa), the roots are green in colour.
2. It commonly does not bear the buds, however, the roots of Aegle, Trichosanthes roots bear vegetative buds for vegetative propagation.
3. At the terminal portion of the root there is a root-cap to provide a protective sheath to the tender root meristem. In Pandanus, the root-cap is distinct and multiple in nature. In aquatic plants root pockets are present.
4. The root bears unicellular hairs, a little behind the apex. These are having thin walls made of cellulose and are short-lived. When older root hairs die off, newer ones are formed towards the apex.
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5. Nodes and internodes are absent in the roots.
6. Lateral roots are developed from an inner layer, i.e., pericycle. So, these are endogenous in origin.