Food reserve of Laminaria is

Options

A. Starch
B. Fat
C. Mannitol
D. Glycogen.

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about the food reserve of Laminaria, which is a type of brown algae.

2. **Understand the Types of Food Reserves**: In biological organisms, food reserves can be stored in various forms such as starch, fat, mannitol, and glycogen.

3. **Analyze the Options**:
- **Starch**: Typically found in higher plants as a food reserve.
- **Fat**: Commonly stored in animal tissues, particularly in adipose tissue.
- **Mannitol**: A sugar alcohol that can be found in some algae, including brown algae.
- **Glycogen**: The primary storage form of glucose in animals.

4. **Connect Laminaria to Its Food Reserve**:
- Laminaria, being a brown algae, stores its food in the form of complex carbohydrates.
- The specific forms of these carbohydrates in brown algae include laminarin and mannitol.

5. **Select the Correct Answer**: Since mannitol is identified as a food reserve in Laminaria, the correct answer is **mannitol**.

**Final Answer**: The food reserve of Laminaria is **mannitol**.

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