The document discusses key biomolecules found in cells, including carbohydrates, lipids, proteins, and nucleic acids. Carbohydrates include sugars, starches, and cellulose and serve as energy sources. Lipids are made of fatty acids and glycerol and function to store energy and insulate the body. Proteins are made of amino acids linked together and serve structural, enzymatic, and other functions. Nucleic acids store and transmit genetic information.