Maximal size in terms of wall thickening and protoplasmic modification are achieved by -

Options

A. Cells of divisional phase
B. Cells of maturation phase
C. Cells of elongation phase
D. Cells of meristematic tissue

Answer

To determine which phase achieves maximal size in terms of wall thickening and protoplasmic modification, we can analyze each option based on the information provided in the video transcript.

### Step-by-Step Solution:

1. **Understanding the Phases of Cell Growth**:
- **Meristematic Phase**: This phase is characterized by active cell division. Cells are small and do not have significant wall thickening or protoplasmic modification since they are primarily dividing.
- **Elongation Phase**: In this phase, cells increase in size primarily through elongation. While there is some growth, it is not focused on wall thickening or protoplasmic modification.
- **Maturation Phase**: This phase is where cells stop dividing and begin to mature. During maturation, cells undergo modifications, including wall thickening and changes in protoplasm, leading to a more developed structure.

2. **Analyzing Each Option**:
- **Option 1 - Cell of Division Phase**: This phase involves active division and does not contribute to maximal size in terms of wall thickening or protoplasmic modification.
- **Option 2 - Cell of Maturation Phase**: This phase is where cells achieve maximal size due to wall thickening and protoplasmic changes. This is the correct answer.
- **Option 3 - Cell of Elongation Phase**: Although cells grow in size, the focus is on elongation rather than thickening of the walls or protoplasmic modifications.
- **Option 4 - Cell of Meristematic Phase**: Similar to the division phase, this phase is focused on division and does not contribute to maximal size.

3. **Conclusion**: Based on the analysis, the maximal size in terms of wall thickening and protoplasmic modification is achieved by the **Cell of Maturation Phase**.

### Final Answer:
The correct answer is **Option 2: Cell of Maturation Phase**.