Two biological important groups of macromolecules with unique characteristics are the carbohydrates and proteins.
The carbohydrates are the most common font of food energy that the living beings use, being present in fruits, vegetables, bread, and so on, in addition to being energy storage molecules (glucose, starch). The carbohydrates are biomolecules made of atoms of carbon, oxygen, and hydrogen that are linked by glycosidic bonds to form the more complex forms of sugars (polymers).
While the proteins are biomolecules that work in cells as enzymes, structural functions, protection, and so on, being obtained in their polymers form in food or made by the body during the protein synthesis process. Those molecules are made by the union of amino acids (monomers base) by peptide bonds (small chains of amino acids link between each other to form a larger protein molecule), being important in the formation of protein mass in the body and in several metabolic reactions indispensable to life.