Floridean starch is the reserve food material which of the following orgaisms?

Options

A. Celidium
B. Sargassum
C. Spirogyra
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding Floridean Starch**: Floridean starch is a type of reserve food material found in certain types of algae. It is structurally similar to amylopectin, which is a component of starch and glycogen.

2. **Identifying the Organisms**: The question provides four options: Gelidium, Sargassum, Spirochera, and "all of these". We need to determine which of these organisms contains Floridean starch as their reserve food material.

3. **Analyzing Each Option**:
- **Gelidium**: This is a type of red algae, which belongs to the Rhodophyceae class. Red algae are known to store Floridean starch.
- **Sargassum**: This is a type of brown algae. The reserve food material in brown algae is typically laminarin or mannitol, not Floridean starch.
- **Spirochera**: This is a green algae. Green algae usually store starch as their reserve food, but not Floridean starch.

4. **Conclusion**: Based on the analysis, only Gelidium, which is a red algae, contains Floridean starch as its reserve food material. Therefore, the correct answer is Gelidium.

**Final Answer**: Gelidium

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