Bioenergetics I: Concept of free energy
- Bioenergetics is the quantitative study of energy transductions in living system. OR
- Quantitative study of energy transformation including the nature and function of the chemical processes underlying these transformations.
Biological Energy Transformations Obey the Laws of Thermodynamics
- The first law of thermodynamics “the principle of the conservation of energy”
- For any physical or chemical change, the total amount of energy in the universe remains constant; energy may change its forms or it may be transported from one region to another, but it cannot be created or destroyed
The second law is the principle of randomness
- The universe always moves toward increasing disorder “in all natural processes, the entropy of the universe increases”.
- Living organisms operate strictly within the principles of law of randomness.
- To understand the applications of the second law to biological systems, we must first define those systems and their surroundings.
- The reacting system and its surroundings together constitute the universe.
- Isolated or closed systems, in which no material or energy is exchanged with the surroundings. For examples, in the laboratory, some chemical or physical processes