AP BIOLOGY

Detailed explanation-1: -Flowing water can move rocks, causing them to rub together and wear down into rounded shapes. When plants grow in cracks in a rock, their roots can widen the cracks and force the rock apart. Rainwater fills small cracks in a rock. As the water freezes, it expands, widening the cracks and splitting apart the rock.

Detailed explanation-2: -When you throw a rock into a river, it pushes water out of the way, making a ripple that moves away from where it landed. As the rock falls deeper into the river, the water near the surface rushes back to fill in the space it left behind.

Detailed explanation-3: -Just like a sponge, porous rocks have the ability to absorb water and other liquids. These rocks, including pumice and sandstone, increase in weight and size as they take in water. You can find out which types of rocks absorb water best by testing for porosity.

Detailed explanation-4: -When water (e.g. rainwater) mixes with carbon dioxide gas in the air or in air pockets in soil, a weak acid solution, called carbonic acid, is produced. When carbonic acid flows through the cracks of some rocks, it chemically reacts with the rock causing some of it to dissolve.