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[Aj: ABA plays an important role in plan...

[Aj: ABA plays an important role in plants during water stress and drought conditions.
[R]: Exogenously applied ABA promotes stomatal closing.

A

If both A and R are true and R is the correct explanation of A

B

If both A and R are true but R is not the correct explanation of A

C

If A is true and R is false

D

If both A and R are false

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To solve the question regarding the assertion and reason about abscisic acid (ABA) and its role in plants during water stress and drought conditions, we can follow these steps: ### Step-by-Step Solution: 1. **Understand the Assertion**: - The assertion states that "ABA plays an important role in plants during water stress and drought conditions." - ABA, or abscisic acid, is indeed a crucial plant hormone that helps plants respond to various stress conditions, including drought and water stress. 2. **Understand the Reason**: - The reason given is that "exogenously applied ABA promotes stomatal closing." - This statement is true because ABA is known to induce stomatal closure, which helps reduce water loss during stressful conditions. 3. **Evaluate the Relationship**: - While both the assertion and the reason are true, we need to determine if the reason correctly explains the assertion. - The assertion highlights the overall role of ABA in managing water stress, while the reason specifically addresses one of its functions (stomatal closing). 4. **Conclusion**: - Since both statements are true, but the reason does not fully explain why ABA is important during water stress (it is just one of its functions), we conclude that the assertion is true and the reason is also true, but it is not the correct explanation for the assertion. 5. **Select the Correct Option**: - Based on the evaluation, the correct option is: "Both assertion and reason are true, but the reason is not the correct explanation of the assertion." ### Final Answer: The correct option is **B**: Both assertion and reason are true, but the reason is not the correct explanation of the assertion. ---
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TRUEMEN BIOLOGY ENGLISH-Plant Physiology -ASSERTION AND REASON
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  2. [A]: Fundamental factor in the vernalization is low temperature. [R...

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  3. [Aj: ABA plays an important role in plants during water stress and dro...

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  4. (A]: Cytokinins help in retention of chlorophyll and delayed senescenc...

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  5. [A]: The germination of lettuce seeds is stimulated by red light and i...

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  6. [A]: The far-red form of the phytochromes ab- sorb light at 740 nm. ...

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  7. [A]: Elongation and division of cells are pro- moted by gibberellins. ...

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  8. [A]: Senescence effect can be reversed by cytokinin. [R]: The loss ...

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  9. [A]: Wilting occurs due to loss in turgidity. [R]: Turgor pressure c...

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  10. [A]: Plasmolysis is seen by both living and dead cells. [R]: Both ty...

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  11. [A]: The water is absorbed by the root and moves into the stem. [R]...

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  12. [A]: Sulphur stabilizes protein structure. [R]: It does not partici...

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  13. [A]: Stomata remain open during day [R]: Stomata help in gaseous exc...

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  14. [A]: The nitrogen content of the plant cannot be detected accurately b...

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  15. [A]: Submerged plants, get CO2 in-the form of CO3^(-) & HCO3^(-3) [R...

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  16. [A]: The evolution of molecular oxygen is con- cerned with photosystem...

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  17. [A]: Antitranspirants are material applied to plants for retarding tra...

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  18. Assertion. Calcium deficiency symptoms first appear in the apical regi...

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  19. Assertion: Deficiency of sulpur causes chlorosis in plants Reason : ...

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  20. Assertion : Water and mineral uptake by root hairs from the soil occur...

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