Living creatures need to repair and maintain their structures. Since, all these structures are made up of molecules, they must move molecules around all the time. Thus, molecular movement is required. for respiration molecular movement is needed because while the respiration process goes on the oxygen inhaled is to be carried to the each cell of our body.thus molecular movement is required in living organisms the break down of water molecule during the process of photosynthesis, release of energy from glucose molecule, movement of solute molecules to regulates stomatal closure & opening. All these are the examples of molecular movement which regulate the important functions like respiration, photosynthesis etc.