In tissue culture experiments, leaf mesophyll cells are put in a culture medium to form callus. This phenomenon may be called as

Question

Accepted Answer

A. 1. Recall what happens to **differentiated plant cells** during tissue culture.
Living differentiated cells, such as leaf mesophyll cells, have normally lost the capacity to divide.

2. Identify the process that lets them regain this ability.
When placed in a culture medium under suitable conditions, these cells can **regain the capacity to divide**, and this reversal is called **dedifferentiation**.

3. Distinguish it from the other options.
**Differentiation** is the opposite process (a cell becoming specialized), **development** refers to the overall growth of an organism, and **senescence** refers to aging — none describe cells regaining division capacity.

Hence, the answer is **A. Dedifferentiation**.