The term used to describe the hereditary material in organisms is DNA, or deoxyribonucleic acid. DNA contains the genetic instructions necessary for the development, functioning, growth, and reproduction of all known living organisms and many viruses. Its structure is a double helix formed by nucleotide sequences, which encode genes. These genes direct the synthesis of proteins, influencing an organism's traits and biological processes. DNA's ability to replicate ensures its transmission from one generation to the next, underpinning the principles of inheritance.