Velamen is found in

Options

A. roots of screwpine
B. aerial and terrestrial roots of orchids
C. leaves of Ficus elastic
D. aerial roots of orchids

Explanation

**Step-by-Step Solution:**

1. **Understanding the Term "Velamen":**
- Velamen is a specialized tissue found in certain plants. It is primarily associated with the roots of epiphytic plants, which are plants that grow on other plants.

2. **Identifying Epiphytic Plants:**
- Epiphytic plants, such as orchids, grow on other plants for support and do not derive nutrients from them. They are often referred to as "space parasites" because they occupy space on other plants.

3. **Types of Roots in Epiphytic Plants:**
- Epiphytic plants have three types of roots:
- Clinging roots: For fixation to the host plant.
- Absorbing roots: For absorbing mineral nutrients from the soil.
- Aerial or epiphytic roots: These roots hang down in the air and are specifically associated with the velamen.

4. **Characteristics of Aerial Roots:**
- Aerial roots of epiphytes are thick, irregular, and lack root caps and root hairs.
- They are covered with a layer of dead spongy tissue known as velamen.

5. **Function of Velamen:**
- The velamen helps the aerial roots absorb water from the moist atmosphere, particularly during rain. This adaptation is crucial for the survival of epiphytic plants in their natural habitats.

6. **Conclusion:**
- Based on the above information, velamen is found in the aerial roots of orchids (and other epiphytic plants like Vanda and Dendrobium). Therefore, the correct answer to the question is that velamen is found in orchids.

**Final Answer:**
Velamen is found in the aerial roots of orchids.

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