All life processes obey the laws of chemistry and physics.
In the behavior of molecules, atoms, and subatomic particles lies the key to such complex biological phenomena as the trapping and storing of solar energy by green plants, the extraciton of useable energy from organic nutrients, the growth and developement of organisms, the pattern of genetic ingeritence, and the regulation of the activities of living cells. All the matter in the universe is composed of basic substances called elements . These elements can be further divided into atoms , which are made up of protons , neutrons , and electrons . These fundamental particles all seek stability by joining together to complete their outer shells, or as unstable isotopes give off parts of themselves to reach a more stable state. Some isotopes tend to decay to a more stable form by giving off various paricles such as alpha particles, beta particles, and photons, often called gamma radiation.