Lipid - A broad group of molecules including fats and waxes that are insoluble in water and are an important part of living cells.⏎
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.⏎