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Assertion:- Eugienoids are mixotrophs ...

Assertion`:-` Eugienoids are mixotrophs
They are photosynthetic in presence of light and when deprived of sunlight they survive predating on other smaller organisms

A

If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.

B

If both Assertion & Reason are True but Reason is not a correct explanation of the Assertiion.

C

If Assertion is True but the Reason is False.

D

If both Assertion & Reason are False

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### Step-by-Step Solution: 1. **Understanding the Assertion**: The assertion states that "Euglenoids are mixotrophs." We need to analyze what mixotrophs are. Mixotrophs are organisms that can obtain their nutrition through both photosynthesis (like plants) and heterotrophy (like animals). 2. **Analyzing Euglenoids**: Euglenoids, particularly the genus Euglena, are known for their ability to perform photosynthesis when light is available. This is due to the presence of chloroplasts in their cells, which allow them to convert light energy into chemical energy. 3. **Behavior in Absence of Light**: The assertion claims that when deprived of sunlight, euglenoids can survive by preying on smaller organisms. However, this is not entirely accurate. While euglenoids can switch their mode of nutrition in the absence of light, they do not primarily prey on other organisms. Instead, they typically rely on saprotrophic nutrition, where they obtain nutrients from decaying organic matter. 4. **Conclusion on Assertion and Reason**: Based on the analysis: - The assertion that "Euglenoids are mixotrophs" is **correct** because they can perform both photosynthesis and saprotrophic nutrition. - The reason provided, stating they survive by predating on smaller organisms, is **incorrect** because they primarily rely on saprotrophic nutrition when light is not available. 5. **Final Answer**: Therefore, the assertion is true, but the reason is false.
### Step-by-Step Solution: 1. **Understanding the Assertion**: The assertion states that "Euglenoids are mixotrophs." We need to analyze what mixotrophs are. Mixotrophs are organisms that can obtain their nutrition through both photosynthesis (like plants) and heterotrophy (like animals). 2. **Analyzing Euglenoids**: Euglenoids, particularly the genus Euglena, are known for their ability to perform photosynthesis when light is available. This is due to the presence of chloroplasts in their cells, which allow them to convert light energy into chemical energy. 3. **Behavior in Absence of Light**: The assertion claims that when deprived of sunlight, euglenoids can survive by preying on smaller organisms. However, this is not entirely accurate. While euglenoids can switch their mode of nutrition in the absence of light, they do not primarily prey on other organisms. Instead, they typically rely on saprotrophic nutrition, where they obtain nutrients from decaying organic matter. ...
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