Germ Theory - A theory in medicine stating that microorganisms are the causative agents of infectious, contagious diseases.⏎
Habitat - The specific geographical area or physical environment that is inhabited by an organism or a population of organisms.⏎
Mucous Membrane - The moist linings of body passages and internal cavities involved with absorption and secretion of substances.⏎
Microbe - Sometimes referred to as a microorganism, a microbe is an organism that is microscopic and thus invisible to the naked eye. ⏎
Meningeal Infection - An infection of the protective membranes that cover the brain and spinal cord, known collectively as the meninges.⏎