Mature differentiated cells revert to meristematic activity to form callus by

Options

A. dedifferentiation
B. differentiation
C. cyto differentiation
D. redifferentiation

Answer

To answer the question regarding how mature differentiated cells revert to meristematic activity to form callus, we can break down the process into several steps:

### Step-by-Step Solution:

1. **Understanding Callus Formation**:
- Callus is a mass of undifferentiated cells that forms at the site of injury or in tissue culture. It is essential for plant regeneration and is primarily composed of parenchyma cells.

**Hint**: Recall that callus formation is a response to injury or stress in plants.

2. **Cell Differentiation and Meristematic Activity**:
- Mature differentiated cells in plants have specific functions (like photosynthesis, nutrient storage, etc.). However, under certain conditions, these cells can revert to a less specialized state, similar to meristematic cells, which are capable of continuous division.

**Hint**: Think about how cells can change their roles based on environmental conditions.

3. **Induction of Meristematic Activity**:
- The reversion of mature cells to a meristematic state is often induced by specific growth regulators or hormones, such as auxins and cytokinins. These hormones stimulate the cells to divide and form a callus.

**Hint**: Remember the role of plant hormones in regulating growth and development.

4. **Tissue Culture Techniques**:
- In laboratory settings, tissue culture techniques are used to promote callus formation. This involves placing plant tissues in a nutrient medium supplemented with the appropriate hormones, which encourages the cells to dedifferentiate and proliferate.

**Hint**: Consider how scientists manipulate plant growth in controlled environments.

5. **Formation of Callus**:
- As the cells divide and proliferate, they form a callus. This callus can then be induced to differentiate into various plant tissues, leading to the regeneration of whole plants.

**Hint**: Think about the final outcome of the callus formation process in plant tissue culture.

### Summary:
Mature differentiated cells can revert to meristematic activity and form callus through the influence of growth regulators, particularly in response to specific conditions or treatments in tissue culture. This process allows for the regeneration of plant tissues and is crucial in various agricultural and horticultural applications.

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