First stated as a method for understanding the basis of biological events, molecular biology seeks to understand how organisms work by delving into the structure and function of individual molecules and how these molecules interact with one another and with the larger environment. According to this book understanding how the chemicals that make up cells impact the behavior of living things is a central goal of molecular biology and genetics. To understand how these molecules work in the dynamic environment of a live cell, biologists use a wide range of molecular and genetic techniques.These methods are being used by groups in our department to investigate a broad range of issues, including as the basic mechanisms governing transcription and translation as well as pathways involved in signal transduction. Among them are the role of the senses of sight and smell and how genetic diversity in wild populations influences evolution. Although the systems being studied include a variety of model species, including bacteria, the yeast, slime molds, worms, the fruit flies, zebrafish, and mice, the findings from these research have some direct or indirect relevance to human health. This book covers the key topics in cell biology, genetics, molecular biology, evolution, and ecology, such as the structure and function of nucleic acids, a general review of cells, and DNA replication with knowledge of genetics and their evolutionary histories.