2Replication of Genetic Information
As the smallest units of organisms, cells share the single basic property/function of dividing and multiplying to create progeny cells. All cellular components must be doubled in number before a cell can divide, but DNA, a genetic material, has the distinctive characteristic of existing as a single molecule in each cell. Since DNA molecules carry the full genetic information of the organisms to which they belong, a DNA molecule from the parent cell must be accurately replicated (i.e., doubled), and the two molecules must be distributed equally to the two daughter cells without fail. In this chapter, we will first learn how genetic-information-carrying DNA consists of two long polymers of small low-molecular units called nucleotides (i.e., double-stranded DNA). We will then learn how DNA has an ingenious mechanism to accurately replicate itself using a strand from the parent DNA as a template - a mechanism not used in the synthesis of other polymers.