23. The Digestive System

Where are bile salts reabsorbed in the small intestine?

Lactose, a sugar found in milk, can only be digested by lactase, a brush border enzyme. All babies produce lactase, but only some adults do. Adults who do not produce lactase are referred to as lactose intolerant, as the presence of undigestible lactose can lead to uncomfortable digestive side effects such as gas and diarrhea. Based on your understanding of the small intestine, where would you expect to find the most lactase in babies and those adults that can digest lactose?

Celiac disease is a condition where the body has an abnormal immune response to the protein gluten found in wheat and other grains. A result of this, the body’s immune response can cause damage to the villi. Based on your knowledge of the small intestine, what function would this this most directly affect?