How does water move in vascular plants? What are the types of driving forces? What are their magnitudes?
In vascular plants, water moves in specialized tissue called the xylem. The xylem consists of dead cells that form tunnels through which water and minerals move upward from the roots. The root pressure and transpiration are the driving forces of the water movement. The root pressure is formed when solutes accumulate at high concentration in the root xylem than other root tissues. Osmosis and osmotic pressure plays important role in the formation of the root pressure. To get water up to all the other organs, the forces of adhesion and cohesion provide the movement of water in the xylem. Transpiration results in the detachment of water molecules from the water surface between cells in the leaf. This process activates the cohesion and adhesion of water in the xylem stimulating its movement.