The genetic material found in living organisms is called DNA (deoxyribonucleic acid). DNA carries the hereditary instructions vital for the growth, development, functioning, and reproduction of all living things. It is structured as a double helix, composed of nucleotides that include a sugar, a phosphate group, and nitrogenous bases (adenine, thymine, cytosine, and guanine). The sequence of these bases encodes the genetic information that determines individual traits and characteristics, making DNA essential for evolution and species diversity.