AP BIOLOGY

Detailed explanation-1: -As soon as you place the paper towels in the glasses, you should notice they start to absorb some of the water. The water starts getting sucked up the paper towel due to capillary action (described in the background section) and eventually starts going down the other side into the empty glass (just like a siphon).

Detailed explanation-2: -Capillary action is all around us every day If you dip a paper towel in water, you will see it “magically” climb up the towel, appearing to ignore gravity. You are seeing capillary action in action, and “climbing up” is about right-the water molecules climb up the towel and drag other water molecules along.

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: -An example of capillary action is when you place a straw into a glass of water. The water seems to climb up the straw before you even place your mouth on the straw. The water has created hydrogen bonds with the surface of the straw, causing the water to adhere to the sides of the straw.