Growth of cell wall during cell elongation takes place by

a. Apposition

b. Intussusception

c. Both A and B

d. Super position

The cell wall in plant cells, primarily composed of cellulose, surrounds and protects the plant’s internal structure. These cell walls are generally dead once the plant matures, but they allow for elongation when the cells are immature.

• Intussusception refers to the growth process where new material is deposited within the existing structure of the cell wall, contributing to cell elongation. This process is responsible for the extension of cell walls as the cell grows.
• On the other hand, Apposition involves the formation of new layers of the cell wall. This type of growth occurs in newly formed cells, where the wall increases by adding fresh layers on top of the existing ones.
• Superposition refers to the act of placing one object directly above another, usually with the intent of making them align or coincide.

Thus, the correct answer is option (B).