Exine of pollen grain

Options

A. is pectolcellulose
B. Exhibits a fascinating array of pattern and designs
C. has micropyle
D. is degraded by enzymes

Answer

### Step-by-Step Solution:

1. **Understanding Pollen Grains**:
- Pollen grains represent the male gametophytes in flowering plants. They are crucial for the process of fertilization.

2. **Structure of Pollen Grains**:
- Pollen grains have a two-layered wall: the outer layer is called the **exine**, and the inner layer is called the **intine**.

3. **Composition of Exine**:
- The exine is primarily made up of **sporopollenin**, which is a robust and resilient substance.

4. **Properties of Exine**:
- The exine is known for its hardness and ability to withstand extreme conditions, including high temperatures and strong acids and alkalis.

5. **Taxonomic Significance**:
- The exine exhibits a fascinating array of patterns and designs, which are significant for the classification and identification of different plant species.

6. **Germ Apertures**:
- The exine contains structures known as **germ apertures**, which are crucial for the formation of the germ tube during the fertilization process.

7. **Evaluating Options**:
- The question provides several options regarding the characteristics of the exine:
- Option 1: "is sporopollenin" - This is correct but not an option.
- Option 2: "exhibits a fascinating array of patterns and designs" - This is correct and significant for taxonomy.
- Option 3: "has micropyle" - This is incorrect; the exine does not have a micropyle.
- Option 4: "is degraded by enzymes" - This is incorrect; the exine is resistant to degradation by enzymes.

8. **Conclusion**:
- The correct answer is that the exine of pollen grains exhibits a fascinating array of patterns and designs, which is of taxonomic significance.