In taxonomizing the body’s various parts (circulatory, respiratory, neurological, etc.), one useful division is: the organs that serve the body’s function as living organisms (reproductive organs, kinetic parts–muscles, sinews, etc.-- breathing, circulation, digestion)—and those which serve to regulate, repair, and maintain the body’s health. Obvious examples are the liver, kidneys, thyroid, etc. – the cleaners, regulators, and repairers. The fact that they very often cross over and do both (the brain, for example) does not nullify the division. And obviously a malfunction in one affects the ability of the other to do its job – AIDS damages the auto-immune system (a health production system), causing a breakdown in, for example, our respiratory system (a general production system).