Compound pollen grains do not occur in

Options

A. Calotropis
B. Orchids
C. Juncus or Cryptostegia
D. Asclepias

Answer

To solve the question "Compound pollen grains do not occur in," we need to analyze the options provided and understand the characteristics of compound pollen grains.

### Step-by-Step Solution:

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

2. **Definition of Compound Pollen Grains**:
- Compound pollen grains, also known as pollinia, consist of more than one pollen grain that are stuck together. This structure is often found in certain plant families.

3. **Analyzing the Options**:
- **Option 1: Calotropis**:
- Calotropis is known to produce compound pollen grains (pollinia). Therefore, this option is incorrect.
- **Option 2: Orchids**:
- Orchids also produce compound pollen grains (pollinia). Hence, this option is also incorrect.
- **Option 3: Juncus**:
- Juncus is a genus of plants that does not produce compound pollen grains. This option is likely correct.
- **Option 4: Cryptostegia**:
- Cryptostegia does not produce compound pollen grains either. This option is also likely correct.
- **Option 5: Asclepias**:
- Asclepias is known to produce compound pollen grains (pollinia). Therefore, this option is incorrect.

4. **Conclusion**:
- Based on the analysis, the correct answer to the question "Compound pollen grains do not occur in" is **Juncus and Cryptostegia**.

### Final Answer:
Compound pollen grains do not occur in **Juncus and Cryptostegia**.

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