So, proteins is yet another type of organic macromolecule that is also a polymer that we ingest when we eat our food. So proteins are another type of macromolecules that we ingest when we eat. So proteins are polymers that consist of individual units we call amino acids, which contain not only oxygen and carbon and hydrogen, but they also contain nitrogen. Now, the bonds that connect these individual monomers, our amino acids, are called peptide bonds. And proteins are usually called polypeptides, which means they consist of many of these peptide bonds and many of these amino acids. Now, just like we have specialized types of enzymes that break down our polymers of carbohydrates, of polysaccharides, we also have specialized types of enzymes in the stomach and a small intestine to basically break down these peptide bonds.