How does water enter and move up the plant?

It moves up through a process known as transpiration. This is when water leaves the through the stomata, creating a negative hydrostatic pressure which pulls the water up through the xylem. The properties of water (also present in Chemistry AS) allow this to happen. The water molecules are bonded together through hydrogen bonds. There are two hydrogen bonds per water molecule. This causes water molecules to "stick together" and is known as cohesion. The water also forms weak bonds to the walls of the xylem, this is known as adhesion. This is cohesion-adhesion. The leaving of water through the stomata and the cohesion-adhesion properties of water create a continuous water column and pulls water up the plant.

The water enters the root hair cells. It travels to the xylem through the apoplastic, symplastic pathways and transmembarne pathways until it gets to the caspian strip. The caspian strip is water proof and forces the water from the apoplastic into the cytosol of the plant cell. From here it can enter the xylem.