Crystal sand found in Atropa cells is made of

Options

A. Calcium oxalate
B. Calcium carbonate
C. Silica
D. Silica and iron

Answer

To answer the question "Crystal sand found in Atropa cells is made of," we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Context**: Understand that the question is asking about a specific structure found in the cells of the Atropa plant.

2. **Define Crystal Sand**: Recognize that "crystal sand" refers to a type of crystalline structure that can be found within plant cells.

3. **Research the Composition**: Based on the information provided, crystal sand can be composed of various substances, including calcium oxalate, calcium carbonate, silica, and iron.

4. **Focus on Calcium Oxalate**: From the video transcript, it is highlighted that the primary component of crystal sand in Atropa cells is calcium oxalate.

5. **Conclusion**: Therefore, the crystal sand found in Atropa cells is primarily made of calcium oxalate.

### Final Answer:
The crystal sand found in Atropa cells is made of **calcium oxalate**.

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