Question

Tuberous roots are found in
(a) Daucus carota
(b) Beta vulgaris
(c) Ipomoea batatas
(d) Raphinus sativus

Answer 1

Hint: It is an enlarged modified lateral root which also functions as a storage organ. The enlarged area of the root-tuber can be formed at the end or middle portion of the root or may involve the entire root too.

Complete answer:
Root tubers act as perennating organs, Such roots are found in plants like Cassava, dahlia, and sweet potato. Ipomoea batatas are the scientific name of sweet potato. They are thick roots that store nutrients over a period of time; while the plant can’t grow. It permits survival from one year to next year. Tuberous root provides energy and nutrients for regrowth during the next growing season, and as a means of asexual reproduction.
Root tubers have a proximal end, which is attached to the old plant and has crown tissue that produces buds, that grow into new stems and new foliage. The other end of the root tuber is the distal end that normally produces unmodified roots.
Tuberous roots are generally biennial in nature; i.e. In the first year, the plant produces tubers and the plant shoots die at the end of the growing season. In the next growing season, the root-tubers then produce new shoots.
So, the answer is ‘Ipomoea batatas’.

Note: Storage roots are further divided into taproots and tuberous roots. Taproots have a large, dominant, central root from which other small adventitious roots branch laterally. Examples of taproot plants include carrots, beetroot, and radish. Tuberous roots have modified lateral storage roots.