All of the following statements are correct for cells of parenchyma, except

Options

A. They are generally isodiametric
B. They have lignified cell walls.
C. They may be spherical, oval, polygonal or elongated in shape.
D. They are the mature cells.

Answer

To solve the question regarding the characteristics of parenchyma cells, we will analyze each statement provided and identify the incorrect one.

### Step-by-Step Solution:

1. **Understanding Parenchyma Cells**:
- Parenchyma cells are a type of simple permanent tissue found in plants. They are generally involved in functions such as storage, photosynthesis, and tissue repair.

2. **Evaluating the First Statement**:
- The first statement mentions that parenchyma cells are generally isodiametric.
- **Analysis**: This is a correct statement. Isodiametric means that the cells can be spherical, oval, or polygonal in shape, indicating that they can have similar dimensions in all directions.

3. **Evaluating the Second Statement**:
- The second statement claims that parenchyma cells are mature cells.
- **Analysis**: This is also a correct statement. Parenchyma cells are indeed mature cells that have reached their final shape, size, and function.

4. **Evaluating the Third Statement**:
- The third statement suggests that parenchyma cells have lignified cell walls.
- **Analysis**: This statement is incorrect. Parenchyma cells have cell walls made of cellulose, not lignin. Lignification is a characteristic of other types of plant cells, such as sclerenchyma.

5. **Conclusion**:
- Based on the analysis, the incorrect statement regarding parenchyma cells is that they have lignified cell walls.

### Final Answer:
The incorrect statement about parenchyma cells is: **They have lignified cell walls.**

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