Question

give any two external feature on the basis of which rhizomes are classified as modified underground stems

Answer 1

ginger and turmeric

Answer 2

Some plants have modified structures that grow underground and perform multiple functions. These could be modified forms of stem, roots and leaves. One of the examples is underground stem called Rhizome.

Rhizome is called underground stem because it contains nutrients secondly it has nodes and internodes. These stems can give rise to vertical shoots that arises from the buds on rhizomes.