23. The Digestive System

As a treatment for certain diagnoses, a section of the small intestine may be removed from a patient. Based on your understanding of their respective functions, a portion of which section of intestine do you think could be removed with the fewest adverse side effects and why?

Which pathway correctly identifies the path of chyme as it moves through 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?

Both Paneth cells and Peyer’s patches are more numerous in the ileum than in the jejunum or the duodenum. Which statement below correctly describes why that may be?

What are the three folds of the small intestine called? What is their purpose?

Regional movements that occur in the small intestine and function to churn and fragment the digestive material are called:

(a) Segmentation

(b) Pendular movements

(c) Peristalsis

(d) Mass movements

(e) Mastication

Which of the following is/are absorbed in the small intestine by the Na+/glucose cotransporter?

a. Glucose

b. Galactose

c. Fructose

d. Both a and b are correct

e. All of the above are correct

Two chyme samples are taken: one from the stomach and one from the duodenum. How could you tell the samples apart using lab techniques?

A lacteal can be found within each:

Gastric bypass surgery involves creating an alternate pathway for food that bypasses the majority of the stomach and a portion of the small intestine to help patients lose weight. A schematic is shown below.

Why do you think it is important to attach the duodenum to the jejunum even if food is no longer passing through it?