Molecular function refers to the specific biochemical activity of a molecule, particularly proteins and nucleic acids. It describes what a molecule does at the molecular level, such as binding to other molecules, catalyzing reactions, or transporting substances. Understanding molecular function is crucial for studying how biological processes occur in living organisms. In the context of biology, molecular functions are often categorized based on their roles in cellular processes. For example, enzymes are proteins that facilitate chemical reactions, while receptors are proteins that receive signals from outside the cell. These functions are essential for maintaining life and are studied in fields like biochemistry and molecular biology.