Question

The lateral branches of roots (dicot) generally originates from
A) Cortex
B) Endodermis
C) Cork cambium
D) Pericycle cells lying against protoxylem

Answer 1

Hint: Roots are one of the most important parts of the plant that help to provide anchorage and also uptake of nutrients and water that is needed for the growth and development of the plant.

Complete answer-
The root is divided broadly into four parts- root cap, root hair, elongation zone and apical meristem. Each of these parts play different roles such as the root cap helps in the penetration of the root into the soil. The root hair helps to absorb nutrients and water from the soil and the apical meristem helps in the formation of new root cells. The roots are known to have endogenous origin being developed from the pericycle which is different from that of stems and leaves which have exogenous origin. The growth of roots depends on several factors such as plant hormone cytokinin which promotes lateral root elongation and auxin which determine lateral root formation. Apart from these several extrinsic factors also play important roles in formation of roots such as gravity, water, oxygen, exposure to light as well as presence of certain minerals such as sulfur, phosphorus, etc.

So the correct option is D) Pericycle cells lying against protoxylem

Note-
Roots are not only important in survival and growth of plants but also have several economical importance such as many root crops serve as important sources of food such as potato, carrot, radish, etc., roots prevent soil erosion and roots also help in vegetative propagation of plants.