Question

Callus is produced from the explant as a result of:

• A. Differentiation
• B. De-differentiation
• C. Re-differentiation
• D. Regeneration

Answer 1

Answer:

B. De-differentiation

• When a plant explant is cultured in vitro on a nutrient medium with appropriate plant growth regulators (such as auxins and cytokinins), the differentiated cells at the cut surface lose their specialized functions and revert to a more primitive, undifferentiated state.

• This process is known as de-differentiation.

• The dedifferentiated cells then divide and form an unorganized mass of cells called the callus. Later, under suitable conditions, the callus can undergo re-differentiation or regeneration to form new roots, shoots, or whole plants.