Application of 2nd law of thermodynamics:

• An energy is transformed from one organism to another (plant to herbivores to carnivores and so on). In this process large part of energy is lost as heat.
• In photosynthetic pigment system( PS1 and PS2) both exothermic and endothermic reaction is required.
• The G=H-TS. When a chemical reaction occurs at constant temperature, the free energy is determined by ▲H reflecting the kind and number of chemical bond and non-constant interaction broken and formed.
• In living system there is anabolic and catabolic process. In anabolism there is less entropy whereas catabolism has higher entropy.

Significance of entropy:

• Entropy is the degree of randomness which is directly proportional to the disorder of system.
• It is the function of thermodynamic probability. Catabolism has higher entropy than anabolism.