Diatoms are unusual in that their vegetative cells are typically

Options

A. haploid
B. diploid
C. both (1) & (2)
D. none of these

Answer

### Step-by-Step Solution:

1. **Understanding Diatoms**: Diatoms are a group of unicellular algae that are known for their unique cell walls made of silica. They are primarily found in aquatic environments, floating in the upper layers of oceans and lakes.

2. **Cell Structure**: The vegetative cells of diatoms possess a distinct structure due to their silica-based cell wall. This characteristic is crucial for their identification and classification.

3. **Reproductive Strategy**: Diatoms reproduce asexually through cell division, but they also have a sexual reproductive phase where haploid gametes are produced.

4. **Ploidy of Vegetative Cells**: The vegetative cells of diatoms are typically diploid. This means they contain two sets of chromosomes.

5. **Gamete Formation**: When conditions are favorable, the diploid vegetative cells undergo meiosis to produce haploid gametes. These gametes are then involved in sexual reproduction.

6. **Conclusion**: Given that the vegetative cells of diatoms are diploid, the correct answer to the question is that diatoms are unusual in that their vegetative cells are typically diploid.

### Final Answer:
The vegetative cells of diatoms are typically **diploid**.

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