Question

The enzyme that breaks down protein during digestion :

• A. Trypsin
• B. Amylase
• C. Pepsin
• D. Chymotrypsin

Hint:

Remember that digestion is a multi-stage process. Pepsin starts protein digestion in the stomach, while trypsin and chymotrypsin continue it in the small intestine. Amylase is for carbohydrate digestion.

Answer 1

The Correct Option is C

Step 1: Understand the role of enzymes in digestion.
Enzymes are biological catalysts that speed up chemical reactions in the body. Different enzymes are specialized to break down specific types of macromolecules like proteins, carbohydrates, and fats. Step 2: Evaluate each option in the context of protein digestion.

(1) Trypsin: Trypsin is a proteolytic enzyme (protease) secreted by the pancreas into the small intestine, where it helps in breaking down proteins and polypeptides.
(2) Amylase: Amylase is an enzyme that breaks down carbohydrates (starches) into simpler sugars. It is found in saliva and pancreatic juice.
(3) Pepsin: Pepsin is a major proteolytic enzyme found in the stomach. It is responsible for initiating protein digestion in the highly acidic environment of the stomach.
(4) Chymotrypsin: Chymotrypsin is another proteolytic enzyme secreted by the pancreas into the small intestine, working alongside trypsin to further break down proteins. Step 3: Determine the enzyme that breaks down protein during digestion from the options.
All of Trypsin, Pepsin, and Chymotrypsin break down protein. However, the question asks for "the enzyme" implying a single best fit from the options, or the most prominent one associated with general protein digestion as opposed to a specific stage or location like the small intestine for Trypsin and Chymotrypsin. Pepsin is the enzyme that begins protein digestion in the stomach. Without additional context about where "during digestion" refers to (e.g., stomach, small intestine), Pepsin is a fundamental answer as it initiates the process. However, if multiple options can be considered correct, usually the "best" or most general answer is expected. Trypsin and Chymotrypsin are also correct in that they break down protein during digestion. But often in basic biology questions, Pepsin is highlighted for its role in the stomach. Given the typical level of these types of questions, Pepsin is the primary enzyme for protein breakdown specifically in the stomach, which is an early and crucial stage of digestion. $$(3) Pepsin$$