Reserve food in Phaeophyceae is

Options

A. laminarin and manitol
B. glycogen and sorbitol
C. floridean starch
D. glucose and starch.

Answer

To determine the reserve food in Phaeophyceae, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Phaeophyceae**:
- Phaeophyceae, commonly known as brown algae, are a group of photosynthetic organisms found in marine environments. They are characterized by their brown pigments.

2. **Identifying Reserve Food**:
- Reserve food refers to the stored energy that organisms use when needed. In algae, this can include various carbohydrates and other compounds.

3. **Analyzing the Options**:
- The question provides several options for the reserve food in Phaeophyceae:
- A) Laminarin and mannitol
- B) Glycogen and sorbitol
- C) Floridean starch and glucose
- D) Starch

4. **Evaluating Each Option**:
- **Option A (Laminarin and mannitol)**: Laminarin is a polysaccharide that is indeed found in brown algae and serves as a storage carbohydrate. Mannitol is a sugar alcohol also present in some brown algae.
- **Option B (Glycogen and sorbitol)**: Glycogen is primarily found in animals and not in brown algae. Sorbitol is a sugar alcohol but is not a primary reserve food in Phaeophyceae.
- **Option C (Floridean starch and glucose)**: Floridean starch is associated with red algae (Rhodophyceae), not brown algae.
- **Option D (Starch)**: While starch is a common reserve food in many plants, it is not the primary reserve food in Phaeophyceae.

5. **Conclusion**:
- After evaluating the options, the correct answer is **Option A: Laminarin and mannitol**. These are the reserve food materials found in Phaeophyceae.

### Final Answer:
The reserve food in Phaeophyceae is **Laminarin and mannitol**.