Final answer:
The phenomenon where water defies gravity and rises through the tree's xylem due to the binding forces between water and the tree's inner walls is called capillary action, which works in conjunction with osmotic pressure and transpiration.
Step-by-step explanation:
The phenomenon referred to when the binding forces between the water atoms and the inner walls of the tree are stronger than gravity, causing the water at the root to rise is known as capillary action. This process involves both adhesion, which is the attraction between water molecules and other molecules such as those that make up the inner walls of the tree, and cohesion, the attraction between water molecules themselves. The combined forces of adhesion and cohesion enable water to travel against gravity through the narrow xylem vessels from the roots to the upper parts of the tree.
Trees also use osmotic pressure to transport water and other nutrients from the roots to the upper branches alongside capillary action. The process of transpiration further aids this movement of water, as water evaporating from the leaves creates a negative pressure that pulls more water up through the plant. It's important to note, however, that while capillary action contributes to this process, transpiration is the primary driver of water movement through the xylem in plants.