Metabolism - The sum total of chemical reactions that occur within a living cell both to build new molecules within the cell and break down and assimilate sources of energy for the cell.⏎
Germ Theory - A theory in medicine stating that microorganisms are the causative agents of infectious, contagious diseases.⏎
Microbe - Sometimes referred to as a microorganism, a microbe is an organism that is microscopic and thus invisible to the naked eye. ⏎
Mucous Membrane - The moist linings of body passages and internal cavities involved with absorption and secretion of substances.⏎