APPLIED RADIOLOGICAL ANATOMY

Detailed explanation-1: -Protein digestion begins when you first start chewing. There are two enzymes in your saliva called amylase and lipase. They mostly break down carbohydrates and fats. Once a protein source reaches your stomach, hydrochloric acid and enzymes called proteases break it down into smaller chains of amino acids.

Detailed explanation-2: -Mechanical digestion of protein begins in the mouth and continues in the stomach and small intestine. Chemical digestion of protein begins in the stomach and ends in the small intestine. The body recycles amino acids to make more proteins.

Detailed explanation-3: -Because of the hydrochloric acid in the stomach, it has a very low pH of 1.5-3.5. The acidity of the stomach causes food proteins to denature, unfolding their three-dimensional structure to reveal just the polypeptide chain. This is the first step of chemical digestion of proteins.

Detailed explanation-4: -Pepsin is a stomach enzyme that serves to digest proteins found in ingested food. Gastric chief cells secrete pepsin as an inactive zymogen called pepsinogen. Parietal cells within the stomach lining secrete hydrochloric acid that lowers the pH of the stomach. A low pH (1.5 to 2) activates pepsin.