Algonquin College Health Program Assessment (AC-HPAT) Practice Exam

Where does the degradation of proteins primarily take place?

1. Large intestine

2. Stomach

3. Small intestine

4. Esophagus

The correct answer is: Stomach

The degradation of proteins primarily takes place in the stomach. This process begins when proteins are first denatured by the acidic environment created by gastric acid (hydrochloric acid) in the stomach. The acid unfolds the protein structures, making them more accessible for enzymatic action. In the stomach, the enzyme pepsin is activated from its precursor pepsinogen and plays a crucial role in breaking down the denatured proteins into smaller peptides. This enzymatic activity is vital for protein digestion, as it reduces proteins to shorter chains of amino acids that can later be further digested in the small intestine. While the small intestine also plays a role in protein digestion with the help of pancreatic enzymes, including trypsin and chymotrypsin, the initial breakdown starts in the stomach. The large intestine and esophagus have different primary functions related to digestion and absorption, but they are not involved in the process of protein degradation like the stomach is.