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 determine the incorrect statement regarding algae, we will analyze each of the provided options step by step.

### Step 1: Analyze the first statement
**Statement:** Algae are largely aquatic organisms.
**Analysis:** This statement is correct. Algae are primarily found in aquatic environments, including both freshwater and marine ecosystems. They are photosynthetic organisms that thrive in these habitats.
**Conclusion:** This statement is correct.

### Step 2: Analyze the second statement
**Statement:** Some of the algae occur in association with sloths.
**Analysis:** This statement is also correct. Certain algae, particularly green algae, can form symbiotic relationships with sloths. The algae benefit from the shelter provided by the sloth's fur, while the sloth gains nutrients and camouflage from the algae.
**Conclusion:** This statement is correct.

### Step 3: Analyze the third statement
**Statement:** The gametes are non-flagellated but similar in size in Spirogyra.
**Analysis:** This statement is correct. In Spirogyra, the gametes are indeed non-flagellated and similar in size. In contrast, in Chlamydomonas, the gametes are flagellated.
**Conclusion:** This statement is correct.

### Step 4: Analyze the fourth statement
**Statement:** Certain marine brown and green algae produce large amounts of hydrochlorides.
**Analysis:** This statement is incorrect. It is actually certain marine brown and red algae that produce large amounts of hydrocolloids (not green algae). Examples include algin from brown algae and carrageenan from red algae.
**Conclusion:** This statement is incorrect.

### Final Conclusion
The incorrect statement regarding algae is: **"Certain marine brown and green algae produce large amounts of hydrochlorides."**

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