Question

Ginger plant has underground stem as
a) Rhizome
b) Bulb
c) Tuber
d) Corm

Answer 1

Hint: Stem is mainly involved in support and growth of lateral appendages. But sometimes, stem gets modified to perform additional functions. This helps the plant for better survival. Different stem modifications are classified as underground, sub-aerial and aerial modifications. Rhizome, bulb, tuber and come are underground modifications of stem.

Complete answer :
A plant is divided into two regions: the shoot and the root. Shoot refers to the part of the plant above the ground whereas the root is underground. The axis of the shoot is the stem. Ginger has a main axis and it grows horizontally on the ground. Rhizome is a prostate, dorsiventral thickened brownish stem. On ginger, brownish lines are visible which represent nodes and internodes. Ginger shows the presence of scaly leaves at nodes. Rhizome remains dormant under soil. The terminal bud gives rise to aerial shoot at the onset of favourable condition. Ginger grows above the ground and runs parallel to the ground. It has scale leaves but lacks chlorophyll. It also stores food. If the growth of rhizome takes place with lateral buds, then it is called sympodial rhizome and if the growth of rhizome takes place through terminal buds, it is called monopodial rhizome. Ginger and lotus are examples of sympodial rhizome and monopodial rhizome respectively.

>Thus, the correct answer is option A- Rhizome.

Additional information: Ginger is a rhizome, which is a modification of stem. It helps the plant to propagate vegetatively. The nodes of ginger are capable of giving rise to roots as well as shoot.

Note: Bulb is a condensed, disc like underground stem and is almost spherical. Example- onion.
Corm is a short, stout, fleshy, upright and thickened underground stem. It is a condensed form of rhizome growing vertically. Example- Colocasia.
Tubers are actually swollen tips or ends of special underground branches that are swollen due to storage of food. They do not produce adventitious roots, hence differ from rhizomes. Example- potato.