Below is a guide to the common questions and key concepts found on this page to help you with your studies. Key Concepts on Page 100

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

: Understanding the sequence of organs: mouth, pharynx, esophagus, stomach, small intestine, and large intestine.

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

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

To remember how enzymes work, think of a . A specific enzyme (the key) will only fit into a specific nutrient molecule (the lock) to break it down.