AP BIOLOGY

Detailed explanation-1: -The major driving force for the transport of water through xylem in plants during day is transpiration. It creates a suctional force called the transpiration pull which pulls the water all the way up even in tall trees. During the night, root pressure is reponsible for transportation of water.

Detailed explanation-2: -The major driving force for transport of water through xylem in plants during the day is transpiration which creates transpiration pull and during the night is root pressure due to the absence of transpiration.

Detailed explanation-3: -The driving force that acts in favour of Transpiration is the difference in Water Vapour between the leaf air spaces and the external air.

Detailed explanation-4: -Driving force: The driving force for transpiration is the difference in water potential between the soil and the atmosphere surrounding the plant. This difference creates a gradient, forcing water to move toward areas with less water.

Detailed explanation-5: -Hence, the only possible driving force for water movement in osmotic membranes is hydraulic pressure gradient.