Protein Digestion and Absorption

Which foodstuffs below are the principal dietary proteins?

• Meat, fish, and eggs

• Legumes, nuts, seeds, and whole grains.

• Dairy products.

• Fruits and vegetables.

How does the stomach prepare dietary proteins for further digestion?

• The stomach uses mechanical digestion to break down proteins into smaller pieces.

• Stomach acid activates pepsinogen to pepsin, which begins protein digestion.

• Proteins are absorbed directly into the bloodstream from the stomach.

• The stomach neutralizes proteins before they enter the intestines.

Mia is studying the absorption of dietary proteins under normal circumstances in the small intestine. Can you explain how this process works?

• Dietary proteins are absorbed as amino acids and small peptides in the small intestine.

• Dietary proteins are absorbed as carbohydrates in the small intestine.

• Proteins are fully digested and absorbed in the stomach.

• Amino acids are excreted without absorption in the small intestine.

Which are the primary animal sources of dietary proteins from?

• Fishes

• Dairy products

• Peas

• Nuts

What is the action of HCl in the stomach during protein digestion?

• Hydrolyzes proteins

• Kills some bacteria

• Denatures proteins

• Synthesizes proteins.

What is the optimum pH for pepsin activity?

• 1-2

• 1.6-2.5

• 5

• 7-8

What are the proteolytic enzymes present in pancreatic juice?

• Trypsin

• Chymotrypsin

• Carboxypeptidases

• CCK

What is the role of enterokinase in protein digestion?

• Hydrolyzes peptide bonds

• Activates trypsinogen

• Hydrolyzes amino acids

• activates proinsulin

What is the absorption rate of L-amino acids compared to D-isomers?

• L-aa more rapidly

• D-isomers more rapidly

• Equal rate

• Not specified

What is the enyzme secreted by serous cells of the stomach for protein digestion?

• Trypsinogen

• Pro-amylase

• Pro -lipase

• Pepsinogen