So once again, to summarize, let's go through the following flow chart. So we begin by ingesting our proteins into the oral cavity. They eventually travel down into the stomach. The high acidity denatures those proteins, and the pepsi breaks those proteins down into smaller polypeptides. Now, those polypeptides travel into the lumen of our small intestine. And in the lumen, these three proteolytic enzymes cleave the polypeptides into small peptides.