- All chemical processes in an organism.
- First law of thermodynamics
- Energy can not be created or destroyed. It can be transferred or transformed.
- Second law of thermodynamics
- Every energy transfer or transformation increases the disorder (entropy) of the universe.
- Catabolic reactions
- Process that release energy from the breakdown of complex molecules into simpler molecule. Example: hydrolysis.
- Anabolic reactions
- Process that consumes energy to create larger molecules from smaller ones. Example: dehydration synthesis.
- Redox reactions
- Chemical reactions with transfers of electrons.
- Chemical reaction where electrons are added to a substance. Reduction = add.
- Chemical reaction where electrons are removed from a substance. Oxidation = lose-.
Organisms are islands of order in a disordered universe.
Maintaining the order requires continual input of energy.