Select an incorrect statement for algae

Options

A. Algae are largely aquatic organisms
B. Some of the algae occur in association with sloth bear
C. The gametes are non-flagellated but similar in size in Spirogyra
D. Certain marine brown and green algae produce large amounts of hydrocolloids

Answer

To solve the question of selecting an incorrect statement for algae, we will analyze each of the provided statements one by one.

### Step-by-Step Solution:

1. **Understanding Algae**:
- Algae are primarily aquatic organisms that can be found in both freshwater and marine environments. They are autotrophic, meaning they can produce their own food through photosynthesis due to the presence of chlorophyll.

2. **Analyzing the Statements**:
- **Statement 1**: "Algae are largely aquatic organisms."
- This statement is correct. Algae are indeed found in aquatic environments.

- **Statement 2**: "Some of the algae occur in association with sloth beer."
- This statement is also correct. Certain algae can be found in association with sloth beer, which refers to a specific ecological relationship.

- **Statement 3**: "The gametes are non-flagellated but similar in size in spirogyra."
- This statement is correct. In Spirogyra, a type of green algae, the gametes are isogamous, meaning they are of similar size and non-flagellated (non-motile).

- **Statement 4**: "Certain marine brown and green algae produce large amounts of hydrocolloids."
- This statement is incorrect. While brown algae do produce hydrocolloids, the reference to "green algae" is misleading. Hydrocolloids are primarily produced by certain marine brown and red algae, not green algae.

3. **Conclusion**:
- After analyzing all the statements, we find that the fourth statement is incorrect. Therefore, the answer to the question is that the fourth statement is the incorrect one regarding algae.

### Final Answer:
The incorrect statement for algae is: "Certain marine brown and green algae produce large amounts of hydrocolloids."

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