AP BIOLOGY

Detailed explanation-1: -Paper towels are made of many small fibers that have gaps in between them. Water gets pulled into these gaps by capillary action-the same phenomenon that allows trees to suck water out of the ground.

Detailed explanation-2: -For example, capillary actions works when placing a thin or narrow straw into a cup of water, we can see the water goes into the straw; the level the water reaches in the narrow straw is higher than the surrounding water in the cup.

Detailed explanation-3: -As you clean up your mess you notice that water is spreading throughout the paper towel. What is going on here? The water is being absorbed, or soaked up, by the paper towel material through a process called capillary action.

Detailed explanation-4: -Capillary action is important for moving water (and all of the things that are dissolved in it) around. It is defined as the movement of water within the spaces of a porous material due to the forces of adhesion, cohesion, and surface tension.

Detailed explanation-5: -Because water molecules like to stick together (cohesion) and like to stick to the walls of the tubes of cellulose (adhesion), they rise up the tubes all the way from the roots to the leaves. Water then evaporates from the leaves, helping to draw up more water from the roots. This process is called capillary action.