23. The Digestive System

Which of the following best describes the role of bile salts in lipid digestion?

a. Bile salts begin chemical digestion of lipids.

b. Bile salts bind to lipids and physically break them apart into monoglycerides and free fatty acids.

c. Bile salts bind to lipids and physically break them apart into smaller pieces.

d. Bile salts interact with pancreatic lipase and catalyze lipid breakdown.

Mr. Williams presents to your clinic with a complaint of abdominal pain in the right upper quadrant. He says that the pain worsens when he eats, particularly when he eats fatty meals. He has noticed that his stool has been an unusual clay color recently. You perform an ultrasound of his abdomen and find that gallstones are blocking his common bile duct, preventing bile from entering the duodenum.

c. Explain why his feces have become a clay color instead of a normal brown color.

Which of the following statements about bile is true?

The primary hormone that triggers the secretion of pancreatic juice and bile is:

a. gastric inhibitory peptide.

b. cholecystokinin.

c. motilin.

d. somatostatin.

Mr. Williams presents to your clinic with a complaint of abdominal pain in the right upper quadrant. He says that the pain worsens when he eats, particularly when he eats fatty meals. He has noticed that his stool has been an unusual clay color recently. You perform an ultrasound of his abdomen and find that gallstones are blocking his common bile duct, preventing bile from entering the duodenum.

a. Why are his symptoms worse when he consumes a high-fat meal? Would you expect his symptoms to worsen or lessen when he consumes a meal consisting only of carbohydrates? Explain.

Mr. Williams presents to your clinic with a complaint of abdominal pain in the right upper quadrant. He says that the pain worsens when he eats, particularly when he eats fatty meals. He has noticed that his stool has been an unusual clay color recently. You perform an ultrasound of his abdomen and find that gallstones are blocking his common bile duct, preventing bile from entering the duodenum.

b. You test Mr. Williams's stool and find high amounts of undigested fats. Explain this finding.

How would the gallbladder respond to an increase in cholecystokinin in the blood?

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

d. The exocrine cells of the pancreas and salivary glands are islet cells.

Which of the following best describes the microscopic structure of the liver?

a. Hexagonal plates of hepatocytes surrounding a central vein with portal triads at each corner

b. Octagonal plates of hepatocytes surrounding a central artery with portal triads at each corner

c. Irregular groups of hepatocytes surrounding a central vein with bile ducts at each corner

d. Hexagonal plates of hepatocytes surrounding a portal vein with bile ducts at each corner

Fill in the blanks: Lipids associate with bile salts in the small intestine to form_____ . In the enterocyte, lipids are packaged with other lipids into______.

The common hepatic duct and main pancreatic duct enter into the:

a. pyloric sphincter.

b. duodenum.

c. ileum.

d. cecum.