Lipids are long chains of carbon and hydrogen molecules. They are oily or waxy.
Proteins are large molecules consisting of one or more chains of amino acids. They provide structure and support for cells.
Carbohydrates are mainly sugars and starches that the body breaks down into glucose. They are the main source of energy in animals.
Nucleic acid is an important class of macromolecules found in all cells and viruses. The functions of nucleic acids have to do with the storage and expression of genetic information.
