Bile and lipase roles in fat processing

Steps:

• Vegetable oil is a lipid requiring emulsification to increase surface area for digestion.
• Bile salts from the liver emulsify fats by breaking them into micelles in the small intestine.
• Pancreatic lipase then hydrolyzes emulsified fats into fatty acids and monoglycerides.
• This process occurs primarily in the duodenum for efficient absorption.

Why A is correct:

• Bile emulsifies vegetable oil by reducing surface tension, while lipase catalyzes its hydrolysis into absorbable components, per lipid digestion physiology.

Why the others are wrong:

• B: Hydrochloric acid denatures proteins in the stomach but does not emulsify or digest lipids; lipase acts post-stomach.
• C: Bile emulsifies fats but lacks protease, which targets proteins, not oils.
• D: Hydrochloric acid activates pepsin for protein digestion, unrelated to lipid emulsification or breakdown.

Final answer: A