Archaea
domain encompassing unicellular organisms that lack both nuclei and membrane-bound organelles and that do not contain peptidoglycan in their cell walls
aseptic technique
method for sterilizing surgical instruments and laboratory tools
Bacteria
domain encompassing unicellular organisms that lack both nuclei and membrane-bound organelles and that contain peptidoglycan in their cell walls
bacterium (plural, bacteria)
unicellular organism lacking a nucleus and membrane-bound organelles within the domain Bacteria
Eukarya
domain consisting of unicellular and multicellular organisms with nuclei and membrane-bound organelles
fungus (plural, fungi)
unicellular or multicellular organism with nuclei and membrane-bound organelles that produces spores and contains chitin in its cell walls
germ theory of disease
theory that infectious diseases are caused by microbes
Gram stain
method of staining used to differentiate types of bacteria based on cell-wall structure
helminth
large, multicellular, worm-like organism that is visible with the naked eye when fully mature and belonging to the phylum Nematoda or Platyhelminthes
Koch's postulates
four criteria that establish a causal relationship between a microorganism and its disease
microorganism
organism too small to be seen without magnification
pasteurization
process of heating liquids or foods to kill microbes that often make people sick or that spoil liquids such as milk
pathogen
disease-causing organism or virus that causes harm to a host organism
prokaryotic
type of cell that does not possess either nuclei or membrane-bound organelles
protozoan (plural, protozoa)
unicellular organism containing nuclei and membrane-bound organelles classified into the kingdom Protozoa
vaccination
technique of exposing an organism to a form of a pathogen to develop immunity against it
virus
infectious agent consisting of a nucleic acid strand within a protein coat