In plants, water is transported through vessels called xylem. The cohesiveness of water molecules allows them to travel up the walls of the vessel. However, for
most plants this is not enough to move the water all the way to the top of the
plant. How do plants overcome the force of gravity and move water to their
upper tissues?
A Root hairs push water through the roots and up into the xylem.
B Plants absorb water through transpiration to supply their upper tissues
with water.
The guard cells surrounding the stomata expand and contract, pushing
water through the xylem.
Water escapes from the leaves through transpiration, creating a vacuum
which pulls water up the xylem.