Which of the following is not a living component of phloem?

Options

A. sieve tubes
B. companion cells
C. phloem parenchyma
D. phloem fibres

Answer

To determine which of the following is not a living component of phloem, we need to analyze the components of phloem and identify which ones are living and which are not.

### Step-by-Step Solution:

1. **Understand Phloem Components**: Phloem is a type of vascular tissue in plants responsible for the transport of nutrients, particularly sucrose. The main components of phloem include:
- Sieve tubes
- Companion cells
- Phloem parenchyma
- Phloem fibers

2. **Identify Living Components**: Among the components listed, we need to identify which ones are living:
- **Sieve tubes**: These are living cells that transport sugars.
- **Companion cells**: These are also living cells that assist sieve tubes in their function.
- **Phloem parenchyma**: These are living cells that serve various functions, including storage and support.

3. **Identify Non-Living Components**: Now, we need to find out which component is not living:
- **Phloem fibers**: These are dead cells, specifically sclerenchyma cells, which provide mechanical support to the plant.

4. **Conclusion**: Based on the analysis, the component that is not a living part of phloem is **phloem fibers**.

### Final Answer:
The component that is not a living component of phloem is **phloem fibers**.

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