Mouth: Mechanical breakdown of food

The digestive system helps us get nutrients from the outside world into our bodies. Technically, the digestive tract is the outside of the body (the mouth and the anus are the holes at either end). So to begin, we’re gonna go over the anatomy of the digestive system, we start at the mouth, which is where ingestion and mechanical breakdown (chewing) of food happens. The mouth and the esophagus are made up of stratified squamous epithelial tissue because the goal here is protection, not absorption or secretion. Saliva moistens the food and starts to break it down (chemical breakdown by an enzymes called amylase (breaks down carbs, is also known as CHO) and lipase (breaks down lipids). Saliva also helps lubricate the food and this helps it travel down the throat more easily.