The stored form of reserve food in brown algae is:

Options

A. laminarin
B. glucose
C. fructose
D. glycogen

Answer

**Step-by-Step Solution:**

1. **Understanding Brown Algae**: Begin by recognizing that brown algae are a group of photosynthetic organisms found in marine environments. They are known for their complex structures and significant ecological roles.

2. **Identifying Reserve Food**: Reserve food in plants is typically stored in specific forms that can be easily utilized when needed. In the case of brown algae, we need to identify what form this reserve food takes.

3. **Evaluating the Options**:
- **Option A: Laminarin**: This is a polysaccharide derived from glucose and is known to be a storage form of carbohydrate in brown algae.
- **Option B: Glucose**: While glucose is a simple sugar and can be used for energy, it is not typically stored in this form in brown algae.
- **Option C: Fructose**: Similar to glucose, fructose is another simple sugar and is not the primary storage form in brown algae.
- **Option D: Glycogen**: This is a storage form of glucose in animals and fungi, but it is not the main storage form in brown algae.

4. **Conclusion**: Based on the information gathered, laminarin is the correct answer as it is specifically known to be the storage form of reserve food in brown algae.

**Final Answer**: The stored form of reserve food in brown algae is **laminarin**.

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