Question

The root pressure theory considers ........... responsible for the ascent of sap.

• A. Gravitational pull
• B. Hydrostatic pressure
• C. Capillary force
• D. None of the above

Answer 1

Answer: (B)

Hydrostatic pressure

The root pressure theory considers that hydrostatic pressure developed in the roots is responsible for pushing the water through the column. It depends on the active accumulation of minerals in the root cells which then causes passive absorption of water creating a high pressure.

It neglects the effect of gravity.

Capillary force is not the driving force in this theory.

Many small herbaceous plants only depend on root pressure for ascent of Sap.

So the correct answer is ' Hydrostatic pressure'.