Tracheid, vessel and sclereids are similar in that they all –

Options

A. Lack secondary walls
B. Conduct water and minerals
C. Function when dead
D. Have open ends

Answer

To answer the question about the similarities between tracheids, vessels, and sclereids, we need to analyze the characteristics of each type of cell.

### Step-by-Step Solution:

1. **Identify the Cell Types**:
- Tracheids: These are long, narrow cells found in the xylem of vascular plants. They help in the conduction of water and minerals.
- Vessels: These are also part of the xylem and are wider than tracheids. They are more efficient in conducting water.
- Sclereids: These are a type of sclerenchyma cell that provides structural support. They can be found in various plant tissues.

2. **Function of Each Cell Type**:
- Tracheids and vessels primarily function in water conduction.
- Sclereids provide mechanical support and protection but do not conduct water.

3. **Determine Common Features**:
- All three cell types (tracheids, vessels, and sclereids) are part of the plant's vascular system.
- They all have thickened secondary cell walls, which contribute to their structural integrity.

4. **Assess the Options**:
- Option 1 (Secondary walls): Incorrect, as sclereids do have secondary walls.
- Option 2 (Conduct water and minerals): Incorrect, since sclereids do not conduct water.
- Option 3 (Function when dead): Correct, as all three types of cells are dead at maturity.
- Option 4 (Half open-ended): Incorrect, as it does not apply to all three types.

5. **Conclusion**: The correct answer is that tracheids, vessels, and sclereids are similar in that they all function when dead.

### Final Answer:
Tracheids, vessels, and sclereids are similar in that they all function when dead.

---