Question

Assertion :In angiosperm, the conduction of water is more efficient, because xylem contain vessels. Reason: Conduction of water by xylem vessels elements is an active process with energy supplied by xylem parenchyma, rich in mitochondria.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.
• C. Assertion is correct but Reason is incorrect.
• D. Both Assertion and Reason are incorrect.

Answer 1

The correct option is C Assertion is correct but Reason is incorrect.

Angiosperms are the only plant groups, which characteristically possess xylem vessels. Other tracheary elements are also present in other plant groups, like pteridophytes and gymnosperms. Bryophytes do not have well vascular tissues. Hence, bryophytes never attain height and plant body tends to remain closer to the surface. This makes all bryophytes dwarf plants. Pteridophytes and gymnosperms are the plants, which have well developed vascular tissue. Consequently, they gain height. Angiosperms have well developed vascular system. A system means a variety of vascular tissues of which xylem vessels are an important type. It has been well demonstrated that the movement of water in all the xylary tissues is due to the transpiration pull generated by the loss of water from the leaves. Hence, the conduction of water is basically a passive process always.

So, the correct answer is option D.