Laws of Thermodynamics In our Universe we find that energy exists in many forms, e.g light, heat, chemical and nuclear etc. Energy describes the ability to influence the Universe and bring about change or to do work. (AKA work done covered later in the energy topic) First Law of Thermodynamics Energy cannot be created or destroyed it can only be changed from one form to another, Therefore the total amount of energy and matter in the Universe remains constant, merely changing from one form to another. The First Law of Thermodynamics (Conservation) states that energy is always conserved, it cannot be created or destroyed. In essence, energy can be converted from one form into another. The Second Law of Thermodynamics (entropy) "in all energy exchanges, if no energy enters or leaves the system, the potential energy of the state will always be less than that of the initial state." This is also commonly referred to as entropy. A machine i.e a wound up toy will run until the potential energy in the spring is converted, and not again until energy is reapplied to the spring to rewind it; the organism will get no more until energy is input again. In the process of energy transfer, some energy will dissipate as heat. Entropy is a measure of disorder: cells are NOT disordered and so have low entropy. The flow of energy maintains order and life. Entropy wins when organisms cease to take in energy and die.