Digestion begins in the mouth where teeth shred the food as a person chews. This process is known as mechanical digestion where food is broken down into smaller pieces. The tongue mixes the food with...

Extracted text: Digestion begins in the mouth where teeth shred the food as a person chews. This process is known as mechanical digestion where food is broken down into smaller pieces. The tongue mixes the food with saliva, which is a mixture of water and enzymes produced by the salivary glands. Saliva begins the process of chemical digestion. It starts the breakdown of starch into simple sugars. After the food becomes soft and moist, the tongue pushes it to the esophagus. Movements of the smooth muscles in the esophagus push the food toward the opening to the stomach. The stomach continues the digestion by squeezing its contents with its muscles. Acids in the stomach begin breaking down protein. The acid also kills bacteria that may have been swallowed with the food. After several hours in the stomach, the food becomes a soupy mixture. The food then passes to the small intestine. Tiny finger-like projections called villi line the small intestine. Digested food passes into the blood through the walls of the villi. Materials that cannot be absorbed in the blood pass into the large intestine. In here, little digestion takes place. The large intestine absorbs water from the undigested material and stores solid wastes until they leave the body when a person visits the comfort room. Questions: 1. What is the author trying to do in the text? What is his purpose for writing? 2. According to the text, in what part of the human body does food digestion begin? In what part does it end? 3. What role do acids in the stomach play in the digestion of food?