Porous wood contains mainly

Options

A. Fibers
B. vessels
C. Tracheids
D. Solid secretion

Answer

To answer the question "Porous wood contains mainly," we will analyze the options provided and determine which one is most relevant to the characteristics of porous wood.

### Step-by-Step Solution:

1. **Understanding Porous Wood**:
- Porous wood refers to wood that has a structure allowing for the passage of air and water. This is typically found in angiosperms (flowering plants).

2. **Identifying Components of Wood**:
- Wood primarily consists of xylem, which is responsible for the conduction of water and minerals from the roots to the leaves. The xylem is made up of various components, including vessels, tracheids, fibers, and parenchyma.

3. **Differentiating Between Components**:
- **Vessels**: These are specialized structures in angiosperms that facilitate efficient water transport. They are larger in diameter compared to tracheids and are more abundant in porous wood.
- **Tracheids**: These are long, narrow cells found in both gymnosperms and angiosperms, but they are not as efficient as vessels in water conduction.
- **Fibers**: These provide structural support but do not play a significant role in water conduction.
- **Parenchyma**: These are involved in storage and metabolic functions but are not primarily responsible for water transport.

4. **Conclusion**:
- Since porous wood is characteristic of angiosperms and is primarily designed for efficient water conduction, the main component of porous wood is **vessels**. Therefore, the correct answer is **vessels**.

### Final Answer:
Porous wood contains mainly **vessels**.

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