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Assertion: The greater part of secondary...

Assertion: The greater part of secondary xylem is lighter in colour and consists of dead elements with highly lignified walls and is called heartwood.
Reason The peripheral region of the secondary xylem is dark brown in colour and is called sapwood.

A

If both assertion and reason are true and reason is the correct explanantion of assertion

B

if both assertion and reason are true but reason is not the correct explanation of assertion.

C

if assertion is true but reason is false.

D

if both assertion and reason are false.

Text Solution

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The correct Answer is:
### Step-by-Step Solution: 1. **Understanding the Assertion**: The assertion states that the greater part of secondary xylem is lighter in color and consists of dead elements with highly lignified walls, referred to as heartwood. This is incorrect because heartwood is typically darker in color due to the accumulation of organic compounds. 2. **Understanding the Reason**: The reason given is that the peripheral region of the secondary xylem is dark brown in color and is called sapwood. This is also incorrect because sapwood is actually lighter in color and is responsible for the conduction of water. 3. **Clarifying the Terms**: - **Heartwood**: This is the central part of the tree, which is darker in color and contains dead xylem cells that have been filled with organic compounds like oils and resins. - **Sapwood**: This is the outer layer of the xylem, which is lighter in color, alive, and actively participates in the conduction of water. 4. **Conclusion**: Since both the assertion and the reason are incorrect, we conclude that the correct answer is that both the assertion and the reason are false. ### Final Answer: Both assertion and reason are false. ---
### Step-by-Step Solution: 1. **Understanding the Assertion**: The assertion states that the greater part of secondary xylem is lighter in color and consists of dead elements with highly lignified walls, referred to as heartwood. This is incorrect because heartwood is typically darker in color due to the accumulation of organic compounds. 2. **Understanding the Reason**: The reason given is that the peripheral region of the secondary xylem is dark brown in color and is called sapwood. This is also incorrect because sapwood is actually lighter in color and is responsible for the conduction of water. 3. **Clarifying the Terms**: - **Heartwood**: This is the central part of the tree, which is darker in color and contains dead xylem cells that have been filled with organic compounds like oils and resins. ...
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