Question: 107 In tissue culture experiments, leaf mesophyll cells are put in a culture medium to form callus. This phenomenon may be called as –
(1) Development
(2) Senescence
(3) Differentiation
(4) Dedifferentiation
Answer: Option (4)
Explanation:
Leaf mesophyll cells are fully differentiated cells with specific structure and function.
When these cells are placed in a suitable culture medium, they lose their specialized characteristics.
They regain the ability to divide actively and form an unorganized mass of cells called callus.
The process by which differentiated cells revert to a meristematic or unspecialized state is known as dedifferentiation.
Hence, formation of callus from leaf mesophyll cells in tissue culture is an example of dedifferentiation.