Question

Transpiration and root pressure cause water to rise in plants by:

• A. Pushing and pulling it, respectively
• B. Pulling it upward
• C. Pulling and pushing it, respectively
• D. Pushing it upward

Answer 1

The correct option is C

Pulling and pushing it, respectively

Transpiration involves the loss of water as vapour from the aerial parts of a plant. This creates a suction pressure in the xylem of the leaves and the stem, which continues to the roots. This is called the transpirational pull, and is responsible for the transport of most of the water from the roots to the rest of the plant. Root pressure is the hydrostatic pressure that develops in the root cells when water enters them by osmosis. This pressure pushes the water upwards, and is often enough for small plants.