In potato tubers, reserve food is starch. It is stachyose in Stachys (Chinese artichoke) tubers. It Jerusalem artichoke (Helianthus tuberosus), the reserve food is in the form of fan shaped crystals composed of

Options

A. Starch
B. Insulin
C. Callose
D. Inulin

Explanation

**Step-by-Step Solution:**

1. **Identify the Reserve Food in Potato Tubers**: The question begins by stating that in potato tubers, the reserve food is starch. This is a well-known fact about potatoes.

2. **Understand the Reserve Food in Stachys (Chinese Artichoke)**: The next part mentions that in Stachys (Chinese artichoke), the reserve food is stachyose. Stachyose is a type of oligosaccharide and is different from starch.

3. **Focus on Jerusalem Artichoke (Helianthus tuberosus)**: The question specifically asks about Jerusalem artichoke, which is scientifically known as Helianthus tuberosus. We need to determine what the reserve food is in this plant.

4. **Analyze the Form of Reserve Food in Jerusalem Artichoke**: It is mentioned that the reserve food in Jerusalem artichoke is in the form of fan-shaped crystals. This indicates that we are looking for a specific carbohydrate that forms such crystals.

5. **Consider the Options Given**: The options provided are:
- A) Starch
- B) Insulin
- C) Kellos
- D) Inulin

6. **Eliminate Incorrect Options**:
- **Starch**: While starch is the reserve food in potatoes, it is not the correct answer for Jerusalem artichoke.
- **Insulin**: This is a hormone produced by animals, not a carbohydrate found in plants, so this option is incorrect.
- **Kellos**: This term does not refer to a known carbohydrate related to reserve food in plants, so it can be eliminated.
- **Inulin**: This is a type of carbohydrate that is known to form fan-shaped crystals and is indeed the reserve food in Jerusalem artichoke.

7. **Conclusion**: Based on the analysis, the reserve food in Jerusalem artichoke (Helianthus tuberosus) is composed of inulin. Therefore, the correct answer is option D) Inulin.

**Final Answer**: The reserve food in Jerusalem artichoke (Helianthus tuberosus) is in the form of fan-shaped crystals composed of **Inulin**.

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