23. The Digestive System

Nutritionists have found that after a heavy meal, the pH of blood increases slightly, especially in the veins that carry blood away from the stomach. What causes this increase in blood pH?

The lamina propria forms part of the:

a. Muscularis externa

b. Submucosa

c. Serosa

d. Mucosa

Which of the following statements about chemical digestion in the stomach are correct:

I. Lipid digestion is begun by enzymes known as lipases.

II. HCl is breaks starches into component monosaccharides. 

III. Proteins are denatured by the protein pepsin.

Match the following terms with the correct definition. 

__Chief cells          

__Parietal cells           

__Gastrin           

__Pyloric sphincter         

__Diffuse neuroendocrine (DNES) cells         

__Gastroesophageal sphincter         

__Pepsin         

__Chyme

a. Hormone that stimulates multiple digestive processes

b. Enzyme that begins protein digestion

c. Produce acid and intrinsic factor

d. Liquid produced as a result of stomach churning

e. Produce pepsinogen

f. Cells in gastric glands that produce hormones

g. Controls passage of bolus from esophagus to stomach

h. Controls passage of stomach contents to duodenum

Which of the following occurs/occur during the cephalic phase of gastric acid secretion?

a. Stimulation of gastrin and histamine release

b. Direct stimulation of parietal cells

c. Inhibition of somatostatin release

d. Both a and b are correct

e. All of the above are correct

Within the gastric glands, which cells would you expect to find closest to the gastric pits?

Mixing of the chyme with gastric juice is achieved via:

Rugae are formed by the two inner most layer of the stomach adjacent to the lumen when the stomach is empty. Knowing this, which stomach layers form the rugae?

A young woman is put through an extensive battery of tests to determine the cause of her stomach pains. She is diagnosed with gastric ulcers. An antihistamine drug is prescribed, and she is sent home. What is the mechanism of her medication? What life-threatening problems can result from a poorly managed ulcer? Why did the clinic doctor warn the woman not to take aspirin?

A surgical procedure known as gastric bypass involves removing all or part of the stomach.

Ms. Anthony has undergone gastric bypass, and her stomach has been removed entirely. She goes out to dinner and eats an extremely large meal. Explain what will happen in her small and large intestine following this meal.

Someone has eaten a meal of buttered toast, cream, and eggs. Which of the following would you expect to happen?

a. Compared to the period shortly after the meal, gastric motility and secretion of HCl decrease when the food reaches the duodenum

b. Gastric motility increases even as the person is chewing the food (before swallowing)

c. Fat will be emulsified in the duodenum by the action of bile

d. All of these

Mark the following statements as true or false. If a statement is false, correct it to make a true statement.

c. Smooth muscle of the stomach contracts when food enters from the esophagus.