Which of the following is an incorrect statement ?

Options

A. Brown algae has chlorophyll a and c, and fucoxanthin
B. In green algae, the cell wall is made up of cellulose.
C. The red algae usually reproduces vegetatively by fragmentation .
D. The food is stored as laminarin in red algae

Answer

To solve the question, we will analyze each option provided to determine which statement is incorrect.

### Step-by-Step Solution:

1. **Evaluate Option 1:**
- The statement claims that brown algae have chlorophyll-a, chlorophyll-c, and phycoxanthin.
- Brown algae (Phaeophyceae) indeed contain chlorophyll-a and chlorophyll-c, as well as the accessory pigment phycoxanthin, which gives them their characteristic brown color.
- **Conclusion:** This statement is **correct**.

2. **Evaluate Option 2:**
- The statement claims that the cell wall of green algae is made up of cellulose.
- Green algae (Chlorophyceae) do have cell walls primarily composed of cellulose, similar to land plants.
- **Conclusion:** This statement is **correct**.

3. **Evaluate Option 3:**
- The statement claims that red algae reproduce vegetatively from fragmentation.
- Red algae (Rhodophyceae) can reproduce both sexually and asexually. They can reproduce asexually through fragmentation, which is a form of vegetative reproduction.
- **Conclusion:** This statement is **correct**.

4. **Evaluate Option 4:**
- The statement claims that the food stored in red algae is laminarin.
- Laminarin is actually a storage carbohydrate found in brown algae, not red algae. Red algae store food in the form of floridean starch.
- **Conclusion:** This statement is **incorrect**.

### Final Answer:
The incorrect statement is **Option 4**: "The food stored in red algae is laminarin."

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