Digestion is not a process of the skeletal system. Metabolism is the beginning of the absorption process, which involves the absorption of nutrients, and the removal of waste from the body. Digestion is a lengthy and involved progression in which the body breaks down food. It begins in your mouth when you take your first bite, you chew, and the food breaks down to go the next phase.
From there, you swallow, and the food travels through the esophagus and into the stomach where more digestive acids break the food down further. Once the food leaves the stomach, it goes into your small intestine and then into the large intestine, or colon, where the liquids and solids are separated and evacuated from the body through urine or stool. The purpose of this process is for your body to extract the vitamins, nutrients, and energy that it needs to function.