Molecular biology is the branch of biology that investigates biological processes at the molecular level, focusing on the structure, function, and interactions of the essential macromolecules that govern life, namely DNA, RNA, and proteins. It explores the fundamental mechanisms of how genetic information is stored in DNA, transcribed into RNA, and translated into proteins—a set of processes known as the central dogma. By examining these molecular interactions and their regulation, this field provides a mechanistic understanding of how cells function, grow, and respond to their environment, bridging the gap between genetics and biochemistry.