MHT CET 202624 AprilMorning Shift
- Exam
- MHT CET
- Year
- 2026
- Date
- 24 April
- Shift
- Morning Shift
- Subject
- Biology
- Chapter
- Transport in Plants
MHT CET 2026 · 24 April · Morning Shift · Biology · Transport in Plants
Which one of the following is NOT an objection against capillarity...
Which one of the following is NOT an objection against capillarity theory of ascent of sap in plants?
Options
- AXylem tracheids compared to capillary tube show closed end walls.
- BThe xylem is not in direct contact with soil water.
- CBecause of capillarity, water can be raised to tall trees.
- DTall trees have wider xylem vessels which do not support capillarity.
Correct answer
C. Because of capillarity, water can be raised to tall trees.
Step-by-step solution
The capillarity theory proposes that the ascent of sap occurs due to capillary action. However, there are several objections to this theory:
1. Xylem vessels are not in direct contact with soil water; they are separated by the root cortex and endodermis.
2. Capillary tubes must be open at both ends, but xylem tracheids have closed end walls.
3. Capillarity can only raise water to a limited height (a few meters) and cannot account for the ascent of sap in tall trees.
4. Capillary rise is inversely proportional to the radius of the tube. Tall trees often have wider xylem vessels, which would result in a lower capillary rise.
The statement 'Because of capillarity, water can be raised to tall trees' is factually incorrect and contradicts the actual objection that capillarity cannot raise water to such heights. Therefore, it is not an objection against the capillarity theory.
Answer: Because of capillarity, water can be raised to tall trees.
1. Xylem vessels are not in direct contact with soil water; they are separated by the root cortex and endodermis.
2. Capillary tubes must be open at both ends, but xylem tracheids have closed end walls.
3. Capillarity can only raise water to a limited height (a few meters) and cannot account for the ascent of sap in tall trees.
4. Capillary rise is inversely proportional to the radius of the tube. Tall trees often have wider xylem vessels, which would result in a lower capillary rise.
The statement 'Because of capillarity, water can be raised to tall trees' is factually incorrect and contradicts the actual objection that capillarity cannot raise water to such heights. Therefore, it is not an objection against the capillarity theory.
Answer: Because of capillarity, water can be raised to tall trees.