Organic molecules are essential to all living things because they are the building blocks of life. These molecules contain carbon and are found in every living organism. Structure - Organic molecules like proteins, carbohydrates, lipids, and nucleic acids make up the structure of cells and tissues in living organisms.Function - They perform important functions. For example,Proteins help build muscles and carry out cell processes.Carbohydrates provide energy.Lipids store energy and make up cell membranes.Nucleic acids (like DNA and RNA) carry genetic information.Growth and Repair - Organic molecules are needed for the growth, repair, and reproduction of cells.