Pollen tube is covered by a membrane made of

Options

A. Pectocellulose
B. Sporopollenin
C. Cellulose
D. Lignocellulose.

Answer

To answer the question "Pollen tube is covered by a membrane made of," we need to analyze the structure of the pollen tube and the materials that compose its membranes.

### Step-by-Step Solution:

1. **Understand the Structure of Pollen Tubes**:
- Pollen tubes are formed from pollen grains during the process of fertilization in plants. They help in the transfer of sperm cells to the ovule.

2. **Identify the Membranes of the Pollen Tube**:
- Pollen tubes have two main layers: the inner layer called the "entire" and the outer layer.

3. **Composition of the Inner Layer (Entine)**:
- The inner layer, or entine, is primarily composed of callose, which is a polysaccharide.

4. **Composition of the Outer Layer**:
- The outer layer is known as the "exine." This layer is made up of pectin and cellulose.

5. **Identify the Correct Answer**:
- The question asks for the material that covers the pollen tube. Since the outer layer is primarily composed of pectocellulose (a combination of pectin and cellulose), the correct answer is **pectocellulose**.

### Final Answer:
The pollen tube is covered by a membrane made of **pectocellulose**.

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