DNAOften referred to as the molecule of life, DNA (deoxyribonucleic acid) is found in almost all living things. It acts as a type of chemical code that contains instructions, known as genes, for how the body and all its different parts grow, develop, function, and maintain themselves. Molecular basis of heredity. It is a complex giant molecule that contains, in chemically coded form, the information needed for a cell to make proteins.