This text investigates the fundamental biological mechanisms of DNA and its role as the primary carrier of genetic information in living organisms. R. M. S. Smellie, a noted biochemist, provides a technical overview of the molecular structure of nucleic acids. The book synthesizes mid-20th-century research to explain how genetic material replicates and directs protein synthesis within the cell.

Experts recognize this work as a concise, foundational text for students entering the field of molecular biology during the mid-20th century. Readers frequently note the academic density of the prose, which assumes a baseline understanding of chemistry and cellular biology.