Companion cells are usually seen associated with
(a) Fibres
(b) Trancheids
(c) Vessels
(d) Sieve cells

Options

A. Fibres
B. Trancheids
C. Vessels
D. Sievenes

Answer

To solve the question regarding the association of companion cells, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Role of Companion Cells**: Companion cells are specialized cells found in the phloem tissue of plants. They play a crucial role in the transport of nutrients, particularly sugars, throughout the plant.

2. **Identify the Structure of Companion Cells**: Companion cells are nucleated cells, meaning they contain a nucleus. This characteristic allows them to support and regulate the function of adjacent cells.

3. **Recognize Associated Cells**: Companion cells are specifically associated with sieve tubes (or sieve cells). Sieve tubes are enucleated cells that lack a nucleus and rely on companion cells for metabolic support and regulation.

4. **Evaluate the Options**:
- (a) Fibres: These are part of the xylem and are not associated with companion cells.
- (b) Tracheids: These are also part of the xylem and are involved in water transport, not associated with companion cells.
- (c) Vessels: Like tracheids, vessels are part of the xylem and are involved in water and mineral transport, not associated with companion cells.
- (d) Sieve cells: These are directly associated with companion cells as they work together in the phloem for nutrient transport.

5. **Select the Correct Answer**: Based on the associations, the correct answer is (d) Sieve cells.

### Final Answer:
Companion cells are usually seen associated with (d) Sieve cells.

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