Which process describes the partial breakdown of proteins in food by digestive enzymes in the stomach during cellular respiration?

• A. Lipolysis
• B. Proteolysis
• C. Glycolysis
• D. Photosynthesis

Answer: (B)

Verified step by step guidance

1. Step 1: Begin by understanding the key terms in the problem. Proteolysis refers to the breakdown of proteins into smaller peptides or amino acids, typically facilitated by enzymes such as pepsin in the stomach.
2. Step 2: Recall the role of digestive enzymes in the stomach. Pepsin is an enzyme that catalyzes the partial breakdown of proteins into smaller polypeptides during digestion, which is a form of proteolysis.
3. Step 3: Eliminate unrelated processes. Lipolysis refers to the breakdown of lipids (fats), glycolysis is the breakdown of glucose during cellular respiration, and photosynthesis is the process by which plants convert light energy into chemical energy. None of these are related to protein digestion.
4. Step 4: Connect the concept of proteolysis to cellular respiration. Proteins broken down into amino acids can enter cellular respiration pathways, such as the Krebs cycle, after deamination.
5. Step 5: Conclude that the correct process describing the partial breakdown of proteins in food by digestive enzymes in the stomach is proteolysis.