Only after these bonds have been broken can the individual molecules begin to move faster, increasing the temperature. This characteristic of water helps living things maintain homeostasis - a stable level of internal conditions. All living things need energy to survive. Energy is defined as the ability to do work or cause change. Within any living system, it is the free energy that is important.
Free energy is available to fuel the cell processes of living things.
All living things need a constant flow of energy into and through their systems. Many of the chemical reactions that transfer energy in living things involve the transfer of electrons. These reactions occur most easily in the polar enviornment of a water solution. Organic compounds contain carbon atoms that are covalently bonded to other carbon atoms and other elements like hydrogen, oxygen, and nitrogen. Carbon atoms are special for two reasons.