Book excerpt: Molecular Genetics, Part II covers the significant developments in various areas of molecular genetics. This book is composed of 10 chapters that also consider the gene expression and regulation of some enzymes. The opening chapters deal with the mechanisms of nucleic acid replication and repair, as well as the structural aspects of the genetic apparatus of viruses and cells. The next chapters explore the patterns and mechanisms of genetic recombination, the in vitro and in vivo experiments to delineate the genetic code, and the initiation of peptide chains in Escherichia coli. These topics are followed by discussions of the mechanism of DNA-dependent RNA synthesis, the regulation of enzyme synthesis in microorganisms, and the regulation of viral replication. The final chapters consider the theoretical and practical aspects of the metabolic regulation in metazoan system and the procedures for the study of DNA-DNA and DNA-RNA interactions. This book will be of great value to molecular geneticists, biochemists, and researchers.