Which of the following tissues is composed of mainly dead cells?
A) Parenchyma
B) collenchyma
C) Aerenchyma
D) Xylem

Options

A. Parenchyma
B. Collenchyma
C. Aerenchyma
D. Xylem

Answer

To solve the question "Which of the following tissues is composed of mainly dead cells?", we need to analyze each option provided:

1. **Identify the types of tissues listed:**
- A) Parenchyma
- B) Collenchyma
- C) Aerenchyma
- D) Xylem

2. **Understand the characteristics of each tissue:**
- **Parenchyma:** This tissue is made up of living cells. It is involved in functions such as storage, photosynthesis, and tissue repair.
- **Collenchyma:** This tissue is also composed of living cells. It provides support to the plant, especially in young stems and leaves.
- **Aerenchyma:** This is a type of parenchyma that contains air spaces and is found in aquatic plants. It is composed of living cells.
- **Xylem:** This tissue is primarily responsible for the transport of water and minerals from the roots to other parts of the plant. Xylem is composed mainly of dead cells, which are specialized for this function.

3. **Determine which option is correct:**
- From the analysis, we see that Parenchyma, Collenchyma, and Aerenchyma are all made up of living cells. The only tissue that is composed mainly of dead cells is Xylem.

4. **Conclusion:**
- Therefore, the correct answer to the question is **D) Xylem**.