Question 1

Which enzyme is primarily responsible for hydrolyzing the sn-1 and sn-3 positions of triacylglycerols (TAGs) during lipid digestion in the small intestine?

Accepted Answer

Pancreatic lipase

Question 2

What is the main function of colipase in lipid digestion?

Accepted Answer

It anchors pancreatic lipase to bile acids on the surface of emulsified lipid droplets.

Question 3

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

Accepted Answer

They emulsify lipids, increasing surface area for enzyme action.

Question 4

A patient with impaired bile acid synthesis would most likely experience which of the following symptoms?

Accepted Answer

Difficulty digesting and absorbing dietary lipids

Question 5

Which hormone stimulates the release of pancreatic lipase and contraction of the gallbladder during lipid digestion?

Accepted Answer

Cholecystokinin (CCK)

Question 6

During lipid absorption, why must coarse emulsion particles be broken down into micelles?

Accepted Answer

Micelles are small enough to diffuse between villi and be absorbed by mucosal cells.

Question 7

Which of the following is TRUE regarding the action of phospholipase A2 during lipid digestion?

Accepted Answer

It acts at the C1 and C2 positions of phospholipids, releasing free fatty acids.

Question 8

Which of the following equations correctly represents the hydrolysis of a triacylglycerol (TAG) by pancreatic lipase?

Accepted Answer

Question 9

Which process is responsible for the breakdown of triglycerides stored in adipose tissue?

Accepted Answer

Lipolysis

Question 10

After absorption into the mucosal cell, how are dietary lipids primarily transported into the circulation?

Accepted Answer

Packaged as chylomicrons and transported via the lymphatic system

Question 11

Which of the following statements about bile acids is CORRECT?

Accepted Answer

Bile acids are continuously made in hepatocytes and stored in the gall bladder.

Question 12

What is the effect of derivatizing bile acids with glycine or taurine?

Accepted Answer

It lowers their pKa, making them more soluble in the acidic environment of the duodenum.

Question 13

Which of the following is a direct product of pancreatic lipase action on triacylglycerols?

Accepted Answer

2-monoacylglycerol and free fatty acids

Question 14

A patient has a genetic deficiency in colipase production. Which of the following would most likely occur?

Accepted Answer

Impaired hydrolysis of dietary triglycerides in the small intestine

Question 15

Which of the following best explains why fat slows the release of food from the stomach?

Accepted Answer

Fat forms a coarse emulsion that is difficult to process, requiring more time for digestion.

Question 16

Which of the following is TRUE regarding the absorption of lipids in the small intestine?

Accepted Answer

Lipids must be broken down into micelles to be absorbed by mucosal cells.

Question 17

Which of the following enzymes is responsible for removing fatty acids from cholesterol esters at low pH?

Accepted Answer

Cholesterol esterase

Question 18

Which of the following is a consequence of bacterial modification of bile acids in the colon?

Accepted Answer

Formation of secondary bile acids associated with increased risk of colonic cancer

Question 19

Which of the following best describes the composition of chylomicrons?

Accepted Answer

Primarily triacylglycerols, plus cholesterol esters and apoproteins

Question 20

Which of the following steps occurs FIRST during the digestion and absorption of dietary lipids?

Accepted Answer

Emulsification of lipids by bile salts

Lipid Digestion and Absorption: Nutritional Biochemistry Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard