A diagram of a tree including its underground roots is shown. A continuously upward moving chain of dots representing water molecules enters the tree through its roots in the soil and exits the tree through its leaves. Water uptake from soil takes place through the roots and Evaporation takes place through the leaves.
Water evaporates from leaves, which stay moist by pulling water up from roots against the pull of gravity. This stretches the water in the tree, but the water molecules resist breaking apart because of tensile strength. Tensile strength results from hydrogen bonds that link water molecules to one another (cohesion) and to cell walls (adhesion). Click on each blinking box to see this.