Recall what happens in physical digestion.

Physical digestion is the process where food is broken down into smaller pieces without chemical changes. Here are the steps:

1. Ingestion: The process begins when food is taken into the mouth.

2. Mastication: The teeth break down the food into smaller pieces through a process called mastication. This increases the surface area of the food for further digestion.

3. Saliva: The salivary glands in the mouth secrete saliva, which moistens the food to make it easier to swallow. Saliva also contains an enzyme called amylase that begins the breakdown of carbohydrates.

4. Swallowing: The tongue pushes the food to the back of the mouth and into the esophagus through a process called swallowing.

5. Peristalsis: The food then travels down the esophagus and into the stomach through a series of muscle contractions known as peristalsis.

6. Stomach: In the stomach, the food is mixed with stomach acid and digestive enzymes through a process called churning. This breaks the food down into a semi-liquid substance called chyme.

7. Small Intestine: The chyme then moves into the small intestine, where it is mixed with more digestive enzymes. The walls of the small intestine absorb the nutrients from the chyme.

8. Large Intestine: Any undigested food passes into the large intestine, where water and electrolytes are absorbed. The remaining waste is formed into feces and stored in the rectum until it is excreted through the anus.

This is the process of physical digestion. It's important to note that physical digestion works in tandem with chemical digestion, where enzymes break down the food on a molecular level.