Which of the following can be made into crystal?

Options

A. A bacterium
B. An Amoeba
C. A virus
D. A sperm

Explanation

**Step-by-Step Solution:**

1. **Understanding the Options**: The question provides four options: bacterium, amoeba, virus, and sperm. We need to determine which of these can be made into crystals.

2. **Identifying Cell Structure**:
- Bacterium, amoeba, and sperm are all types of cells. They have a cellular structure that includes a cell membrane, cytoplasm, and genetic material.
- In contrast, a virus is not considered a cell. It is made up of genetic material (DNA or RNA) enclosed in a protein coat.

3. **Crystallization of Biological Entities**:
- Crystallization typically requires a stable structure. Cells (bacterium, amoeba, sperm) are complex and dynamic, making them unsuitable for crystallization.
- Viruses, on the other hand, have a simpler structure. They consist of genetic material and a protein coat, which allows them to be crystallized.

4. **Historical Example**: The Tobacco Mosaic Virus (TMV) was the first virus to be crystallized, an achievement accomplished by Wendell Meredith Stanley in 1935. This demonstrated that viruses could retain their infectivity even after crystallization.

5. **Conclusion**: Based on the above points, the only option that can be made into crystals is the virus.

**Final Answer**: The virus can be made into crystals.

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