Question

How water in xylem vessels rises up?

• A. The water molecules are also attracted to the wall of xylem vessels.
• B. Water molecules rises and drags other molecules.
• C. Due to cohesive force.
• D. All of the above.

Answer 1

The correct option is D All of the above.

Water tends to rise up inside the narrow tubes by capillary action. This is because of an attraction of water molecules to each other by a week electrostatic force. This is called the cohesive force the water molecules are also attracted to the wall of a glass capillary tube which is similar to the inside of the xylem vessel. Because of this, water rises up in the xylem vessel to some distance up dragging other water molecules present below them. This capillary rise cannot take up water to tall plants though this may be possible in very small plants.