The beautiful diatoms and desmids are placed under

Options

A. chrysophytes
B. dinoflagellates
C. euglenoids
D. slime moulds

Answer

**Step-by-Step Solution:**

1. **Identify the Organisms**: The question refers to diatoms and desmids, which are types of algae.

2. **Classification of Diatoms and Desmids**: Both diatoms and desmids belong to the group of organisms known as "Chrysophyta," which is commonly referred to as the golden algae.

3. **Characteristics of Diatoms**: Diatoms are unicellular algae characterized by their unique silica cell walls, which often have intricate and beautiful patterns. They are known for their role in aquatic ecosystems as primary producers.

4. **Characteristics of Desmids**: Desmids are a group of green algae that are also unicellular and are known for their symmetrical and beautiful shapes. They are primarily found in freshwater environments.

5. **Ecological Role**: Both diatoms and desmids play a significant role in aquatic ecosystems, contributing to the food web and oxygen production through photosynthesis.

6. **Conclusion**: Therefore, diatoms and desmids are classified under the division "Chrysophyta" or golden algae.

**Final Answer**: Diatoms and desmids are placed under the division "Chrysophyta."

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