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[A]: Rubber is obtained from the latex o...

[A]: Rubber is obtained from the latex of Hevea brasiliensis.
[R]: Because secretory canals are abun- dantly found in the secondary phloem

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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The correct Answer is:
**Step-by-Step Solution:** 1. **Understanding the Assertion:** - The assertion states that rubber is obtained from the latex of *Hevea brasiliensis*. This is a well-known fact as *Hevea brasiliensis*, commonly known as the rubber tree, is the primary source of natural rubber. 2. **Understanding the Reason:** - The reason given is that secretory canals are abundantly found in the secondary phloem. This refers to the presence of latticifers, which are specialized cells that transport latex in the rubber tree. 3. **Evaluating the Truth of Each Statement:** - Both the assertion and the reason are true statements. Rubber is indeed harvested from the latex of *Hevea brasiliensis*, and it is true that the secretory canals (latticifers) are found in the secondary phloem of the tree. 4. **Determining the Relationship:** - While both statements are true, the reason does not directly explain the assertion. The assertion is about the source of rubber (the latex), while the reason describes the structure that contains the latex. The presence of secretory canals in the secondary phloem is relevant but does not explain why rubber is obtained from the latex. 5. **Conclusion:** - Therefore, the correct option is that both the 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 Morphology & Reproduction -ASSERTION AND REASON
  1. [A]: The inner most distinict layer of the cortex is called endodermi...

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  2. [A]: Gramineoos type of stomata are found in Gramineae and Cyperaceae....

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  3. [A]: lntercellular spaces are found in mer-isematic cells (R]: The m...

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  4. [A]: Monocot stem has collateral open vascu- lar bundle. [R]: Open ...

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  5. [A]: Root system in hydrophytes is poorly de- veloped. [R]: The con...

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  6. [A]: Aerenchyma is a characteristic of litho- phyte. [R]: It is a sp...

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  7. [A]: Protostele is most simple primitive type of stele. [R]: Accordi...

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  8. [A]: Rubber is obtained from the latex of Hevea brasiliensis. [R]: B...

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  9. [A]: No fibres are found in plants. [R]: Xylem vessels are absent ...

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  10. [A]: Sclerenchyma cells are rarely found in plants. [R]: Sclerencym...

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  11. [A]: Hanstein's dermatogen is not eqyivalent to Haberlandt's Protoderm...

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  12. [A]: Trichomes may occur on all parts of a plant. [R]: Trichomes ei...

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  13. [A]: The vascular cambium is absent in monocots. [R]: The monocots ...

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  14. [A]: In the hydrophytes the Xylem is not differentiated into different...

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  15. [A]: Dicot stem shows secondary growth. [R]: Tissue system is not d...

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  16. Assertion : In woody stems, the amount of heartwood continues year aft...

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  17. [A]: The inner most distinct layer of the cortex is called endodermis...

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  18. [A]: Sieve tube members have abundant cytoplasm but there is no nucleu...

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  19. Assertion : In collateral vascular bundles phloem is situated toward ...

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  20. [A]: Xylem translocates water and dissolved mineral salts from the roo...

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