Question

Assertion: Roots contain no nodes, leaves, and buds.
Reason: Root branches arise endogenously.
(a) Both assertion and reason are true but the reason is not a correct explanation of assertion.
(b) Both assertion and reason are true but the reason is a correct explanation of assertion.
(c) Both assertion and reason and false.
(d) The assertion is true but the reason is false.

Answer 1

Hint Axis of a flowering plant is divided into a root system and shoot system. The root system arises underground whereas the shoot system arises above the ground. Both the root and shoot system consist of branches which help to perform the various functions of the plant.

Complete Answer:
The root is a non-green part of the stem that grows downwards into the soil. It lacks leaves, nodes, and buds, the root branches help in the absorption of water and minerals. Its branches develop usually from the pericycle of the parent root that's why it is endogenous in origin.

Additional information:
The root is divided into five parts root caps, meristematic zone, the zone of elongation, the zone of root hair, and zone of maturation. Root cap present at the tip of root which secretes mucilage and lubricates the passage of root through soil. It also possesses starch grains which are responsible for the perception of gravity. The meristematic zone lies beyond the root cap which is one millimeter in length. The cell of this zone helps to add new cells to the root and root cap. The zone of elongation is 4-7 mm in length which consists of newly formed cells that don't show division. These zones increase the length of root and also possess the power of absorption of water and minerals from the soil. The zone of root hair lies above the region of elongation and bears a cluster of root hairs which is fine tubular in structure. It increases the exposed surface of the root for absorption. With an increase in root hair length, the root hair of the old region shed off. The zone of maturation forms the major part of the root. It is the permanent zone that gives out lateral roots. This zone does not take part in absorption but gives support to the stem and root both.

So, the correct answer is ‘Both assertion and reason are true but the reason is the correct explanation of the assertion’.

Note: Potato and ginger grow inside the soil but they are not considered as root because they consist of nodes and buds hence they are underground stems. In the case of mangrove trees, some root arises out of the soil for respiration by lenticels and pneumatophores.