Write about the mechansim of water movement in plants
Dear student,
The different theories for water transport or water movement in plants-
1.Cohesion-tension-transpiration pull theory proposed by Dixon and Jolly is the accepted theory of water transport in plants.
It has two main features-
a)Water molecules are attracted to each other(cohesion) and forms a continuous channel for water transport. Water molecules are also attracted by xylem elements(adhesion). Thus cohesive and adhesive forces maintains the continuity of water from roots to leaves.
b) The pulling force generated in the xylem elements due to loss of water by transpiration which creates a negative hydrostatic pressure which in turn exerts pulling force which helps in transport of water. This is known as transpiration pull.
2.Root pressure theory-Various ions from the soil are actively transported into the vascular tissues of the roots, water follows and increases the pressure inside the xylem which creates positive pressure known as root pressure and is responsible for pushing water to a small height.
Regards
The different theories for water transport or water movement in plants-
1.Cohesion-tension-transpiration pull theory proposed by Dixon and Jolly is the accepted theory of water transport in plants.
It has two main features-
a)Water molecules are attracted to each other(cohesion) and forms a continuous channel for water transport. Water molecules are also attracted by xylem elements(adhesion). Thus cohesive and adhesive forces maintains the continuity of water from roots to leaves.
b) The pulling force generated in the xylem elements due to loss of water by transpiration which creates a negative hydrostatic pressure which in turn exerts pulling force which helps in transport of water. This is known as transpiration pull.
2.Root pressure theory-Various ions from the soil are actively transported into the vascular tissues of the roots, water follows and increases the pressure inside the xylem which creates positive pressure known as root pressure and is responsible for pushing water to a small height.
Regards