What are the 2 types of interaction of water molecules that allow water to travel upwards in the plants? What other physical process aids in water transport to the top of the trees?
Two types of interaction are:
1. Cohesion − Mutual attraction between water molecules
2. Adhesion − Attraction of water molecules to polar surface (xylem cell wall surfaces).
Transpiration pull is the main force responsible for the upward movement of water and minerals to the top of the tree. This pull is generated in xylem elements due to loss of water from the leaves by transpiration and this loss of water creates a negative hydrostatic pressure that exerts pulling force.