Endopeptidases are enzymes that break down proteins by cleaving peptide bonds within the protein chain. This process helps in the digestion of food and the recycling of proteins in cells. They play a crucial role in various biological processes, including metabolism and cellular signaling. These enzymes are found in many organisms, including humans, where they are produced in the stomach and pancreas. Examples of endopeptidases include pepsin, which works in the acidic environment of the stomach, and trypsin, which functions in the small intestine. Their activity is essential for proper nutrient absorption and overall health.