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Assertion: Xylem vessel is a long cylind...

Assertion: Xylem vessel is a long cylinderical tube like-structure made up of many cells each with ingnified walls.
Reason: Presence of vessels is characteristic feature of gymnosperms

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

AI Generated Solution

The correct Answer is:
**Step-by-Step Solution:** 1. **Understanding the Assertion**: The assertion states that "Xylem vessel is a long cylindrical tube-like structure made up of many cells each with lignified walls." - **Analysis**: This statement is true. Xylem vessels are indeed long, cylindrical structures that facilitate the transport of water and minerals in plants. The walls of these vessels are lignified, which means they contain lignin, a substance that provides strength and rigidity. 2. **Understanding the Reason**: The reason provided is "Presence of vessels is a characteristic feature of gymnosperms." - **Analysis**: This statement is false. Gymnosperms do not possess xylem vessels; instead, they have tracheids for water conduction. The presence of vessels is a characteristic feature of angiosperms (flowering plants), not gymnosperms. 3. **Conclusion**: Since the assertion is true and the reason is false, we conclude that the correct answer to the question is that the assertion is true but the reason is false. 4. **Final Answer**: The correct option is option 3: "Assertion is true, but reason is false." ---
**Step-by-Step Solution:** 1. **Understanding the Assertion**: The assertion states that "Xylem vessel is a long cylindrical tube-like structure made up of many cells each with lignified walls." - **Analysis**: This statement is true. Xylem vessels are indeed long, cylindrical structures that facilitate the transport of water and minerals in plants. The walls of these vessels are lignified, which means they contain lignin, a substance that provides strength and rigidity. 2. **Understanding the Reason**: The reason provided is "Presence of vessels is a characteristic feature of gymnosperms." - **Analysis**: This statement is false. Gymnosperms do not possess xylem vessels; instead, they have tracheids for water conduction. The presence of vessels is a characteristic feature of angiosperms (flowering plants), not gymnosperms. ...
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