AP BIOLOGY

Detailed explanation-1: -The continuous evaporation of water (or transpiration) from the cells of a leaf crates a kind of suction which pulls up water through the xylem vessles. Thus, transpiration helps in the upward movement of water and dissolved minerals from the roots to the leaves through the stem.

Detailed explanation-2: -Complete answer: The upward movement of water from root to leaves in a plant is known as Ascent of sap. It is carried out by xylem tissues that take water and minerals from the roots to the crown.

Detailed explanation-3: -The direction of xylem transport is upwards and unidirectional i.e. from roots to other plant parts. The water column moves only upwards because of the two forces, transpirational pull, and positive root pressure.

Detailed explanation-4: -The movement of water in the xylem is unidirectional and is always upward. The upward movement of water is due to pressure created by transpiration, i.e. transpiration pull.