Pollen grains of Pinus are

Options

A. Monosaccate
B. Bisaccate
C. Trisaccate
D. Non-saccate.

Answer

**Step-by-Step Solution:**

1. **Identify the Subject**: The question pertains to the pollen grains of Pinus, which is a genus of gymnosperms.

2. **Understand the Types of Pollen Grains**: The options provided are:
- a. monosacchate
- b. bisacchate
- c. trisacchate
- d. nonsacchate

3. **Define the Terms**:
- **Monosacchate**: Pollen grains with one sac.
- **Bisacchate**: Pollen grains with two sacs.
- **Trisacchate**: Pollen grains with three sacs.
- **Nonsacchate**: Pollen grains without sacs.

4. **Analyze the Characteristics of Pinus Pollen Grains**: Pollen grains of Pinus are known for their buoyancy, which allows them to float. This buoyancy is attributed to the presence of sacs.

5. **Determine the Correct Option**: Since the pollen grains of Pinus have two sacs, they are classified as bisacchate. Therefore, the correct answer is option b, bisacchate.

6. **Conclusion**: The pollen grains of Pinus are bisacchate due to their structure that aids in buoyancy.

**Final Answer**: The pollen grains of Pinus are bisacchate (option b).

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