Which of the following is not true about 'selereids'?

Options

A. These are groups of living cells
B. These are found in nut shells, guava pulp, pear
C. These are also called stone cells
D. These are form of selerenchyma with fibres

Answer

**Step-by-Step Solution:**

1. **Understanding Sclerites**: Sclerites are specialized cells that are part of the sclerenchyma tissue in plants. They are known for their structural support and protection.

2. **Characteristics of Sclerites**:
- Sclerites are composed of dead cells.
- They have thick cell walls that are often lignified (contain lignin), which provides rigidity and strength.
- They are typically found in various plant structures, including seed coats and the outer layers of fruits.

3. **Function of Sclerites**: The primary functions of sclerites include providing mechanical support to the plant and protecting it from herbivory and environmental stress.

4. **Evaluating the Options**:
- The first option states that sclerites are a group of living cells. This is incorrect because sclerites are made up of dead cells.
- The second option mentions that sclerites are found in nuts, shells, guava pulp, and pears. This is true as they are present in the seed coats of these fruits.
- The third option refers to sclerites as stone cells, which is also correct since they are known for their hard, stone-like structure.
- The fourth option indicates that sclerites form sclerenchyma with fibers, which is accurate as sclerites are a type of sclerenchyma.

5. **Conclusion**: The only statement that is not true about sclerites is that they are a group of living cells. Therefore, this is the correct answer to the question.

**Final Answer**: The statement that is not true about sclerites is: "They are a group of living cells."

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