ABSTRACT
Life depends on the ability of cells to store, retrieve, and translate the genetic instructions required to make and maintain a living organism. This hereditary information is passed on from a cell to its daughter cells at cell division, and from one generation of an organism to the next through the organism's reproductive cells. A deoxyribonucleic acid (DNA) molecule consists of two long polynucleotide chains composed of four types of nucleotide subunits. Each of these chains is known as a DNA chain, or a DNA strand. The ability of each strand of a DNA molecule to act as a template for producing a complementary strand enables a cell to copy, or replicate, its genome before passing it on to its descendants. The complete store of information in an organism's DNA is called its genome, and it specifies all the RNA molecules and proteins that the organism will ever synthesize.
