Macromolecules are just that - large molecules. The four groups of macromolecules, shown in the table below, are essential to the structure and function of a cell.

Group Building Block Large Molecule Function To Identify, Look for . . .
Carbohydrate Monosaccharide Polysaccharide Energy storage, receptors, structure of plant cell wall Made of C,H, and O; –OH's on all carbons except one
Protein Amino acid Polypeptide or protein Enzymes, structure, receptors, transport, and more Contain N, have N-C-C backbone
Nucleic acid Nucleotide Polynucleotide or nucleic acid Information storage and transfer Contain N in rings, nucleotides made of sugar, phosphate and nitrogenous base
Lipid * Glycerol, fatty acids Fats, oils, waxes, phosopholipids, steroids Membrane structure, energy storage, insulation Made of C,H, and O; lots of C-H bonds; may have some C=C bonds (unsaturated); steroids have 4 rings
*Lipids are not polymers.