Which of the following contributes most to transport of water from ground to leaves of a tall tree?
Which of the following contributes most to transport of water from ground to leaves of a tall tree?
The correct option is C cohesion of water and transpiration pull
The correct answer is option C:
Explanation for correct option:
- For small plants root pressure and transpiration pull facilitate water transport from roots to leaves.
- However, in the case of tall trees like pine, cedar etc, the root pressure is too small to do the same.
- Here the cohesive forces of water molecules help in building high surface tension and thus transports the water against gravitational pull to great heights.
Explanation for incorrect option:
Option A
ATP is not required for water movement. Hydrolysis of ATP produces ADP, together with an inorganic phosphate ion (Pi), and the release of free energy.
Option B
Capillary action helps in bringing water up into the roots but capillary action can only "pull" water up a small distance, after which it cannot overcome gravity.
Option D
Root pressure provides a force, which pushes water up the stem but it is not enough to account for the movement of water to leaves at the top of the tallest trees.
Final answer: The cohesion of water and transpiration pull contributes most to the transport of water from the ground to the leaves of a tall tree.
cohesion of water and transpiration pull
The correct answer is option C:
Explanation for correct option:
- For small plants root pressure and transpiration pull facilitate water transport from roots to leaves.
- However, in the case of tall trees like pine, cedar etc, the root pressure is too small to do the same.
- Here the cohesive forces of water molecules help in building high surface tension and thus transports the water against gravitational pull to great heights.
Explanation for incorrect option:
Option A
ATP is not required for water movement. Hydrolysis of ATP produces ADP, together with an inorganic phosphate ion (Pi), and the release of free energy.
Option B
Capillary action helps in bringing water up into the roots but capillary action can only "pull" water up a small distance, after which it cannot overcome gravity.
Option D
Root pressure provides a force, which pushes water up the stem but it is not enough to account for the movement of water to leaves at the top of the tallest trees.
Final answer: The cohesion of water and transpiration pull contributes most to the transport of water from the ground to the leaves of a tall tree.
