Dec 17,  · Organic molecules are the molecules which exist in all living things. They are life‟s building blocks. All things are formed from these organic molecules. There are four categories . Worksheet - Review for biomolecules - Key - Page 1 of 4 Biology 12 - Biologically Important Molecules • Part A: Mix and Match: Match the term on the right with the definition on the left. . Organic molecules are the molecules which exist in all living things. They are life’s building blocks. All things ar