The text under the title „DNA replication “written by Brooker analyses the process in which existing DNA strands are used to make new ones. In this text author explains how the structures of DNA are involved in this process by overviewing bacterial DNA replication and some interesting features of eukaryotic DNA replication.
First chapter presents the basic characteristics of DNA replication. Process begins when two complementary strands unwind and each parental strand is used as template to synthesize new daughter strands acccording to the AT/GC rule. Those strands are identical so they contain the same information. According to the author, some scientists in the late 1950s thought of three models of DNA replication: conservative when parental strands stay together, semiconservative when the new DNA strand consists of one newly made strand and one old strand and dispersive model when DNA contains segments of both parental and newly made strands. Meselson and Stahl proved that DNA replication is semiconservative with an experiment whhere they labeled DNA with heavy and light isotopes of nitrogen and used centrifugation.
Second chapter examines how DNA replication occurs within bacteria. Synthesis begins at a single origin of replication and continues bidirectionally until two replication forks meet each other. Di