Question

The ascent of sap in tall trees is mainly due to

• A. active transport
• B. transpiration pull
• C. guttation

Answer 1

The correct option is B transpiration pull

Transpiration is the loss of water in the form of water vapour from the aerial parts of the plant. Transpiration creates a suction pressure which pulls up water from the xylem of the roots to the stem and then to the leaves. Such a suction force is very essential in tall trees where upward conduction of water is upto height of 100 metres or more.