: Three layers of smooth muscle that churn the food. Serosa : The outer protective covering. Study Tip: The "Enzyme-Substrate" Fit

: Splitting complex organic molecules (proteins, fats, carbohydrates) into simpler, absorbable ones using enzymes. Absorption : Moving nutrients into the blood and lymph. Excretion : Removing undigested food remains from the body.

: Contains glands that secrete gastric juice and protective mucus. Submucosa : Contains blood vessels and nerves.

The textbook details that the stomach wall consists of four layers:

The 100th page of the typically focuses on the Digestive System , specifically the anatomy and functions of the digestive tract and the roles of various digestive glands .