Question

When the roots are alternatively swollen and constricted, presenting a beaded appearance, they are called as
A.Moniliform
B. Annulated
C. Tuberous
D. Nodulose

Answer 1

Hint: Adventitious roots are the roots that undergo modifications in response to external or internal stimuli. They undertake different forms in such a response.
These modifications take place for storage, additional support, nutrition, and respiration. Adventitious roots are of the following types- tuberous, fasciculated, moniliform, nodulose, and annulated.

Complete answer:

> Option (A)- Moniliform
Moniliform are adventitious roots that are swollen at regular intervals giving the appearance of beads of a necklace. Therefore, they are also known as beaded roots. For example, Baseila Rubra (India spinach), Momordica, and some grasses.

> Option (B) - annulated
Annulated roots are the type of adventitious roots that appear to be formed by the numerous discs placed one above the other. For example, Ipecac.

> Option (C)- Tuberous
Tuberous roots are a type of adventitious roots that are swollen. These are irregularly shaped tubers which arise singly from each node. For example Sweet potato.

> Option (D)- Nodulose
Nodulose roots are also adventitious roots. They are the slender roots that are swollen abruptly at the apex. For example Mango-ginger.

Hence, The correct answer is option (A).

Note: Adventitious roots are plant roots that are formed from any non-root tissue. They are produced both during normal development, for example- crown roots on cereals and nodal roots on strawberry, and also in response to stress conditions, like flooding, nutrient deprivation, and wounding.