Comprehensive Microbiology Glossary – Final Exam Study
Guide of Key Terms and Definitions for Pathogens, Immunity,
Lab Techniques, and Disease Processes
Microbiology - correct answer The scientific study of microorganisms, including bacteria,
archaea, viruses, fungi, protozoa, and algae.
Microorganisms - correct answer Living organisms that are too small to be seen by the naked
eye and require microscopy for visualization.
Prokaryote - correct answer Organism lacking a true nucleus and membrane-bound organelles;
includes bacteria and archaea.
Eukaryote - correct answer Organism with cells containing a true nucleus and membrane-
bound organelles.
Domain - correct answer Highest taxonomic rank of organisms; three domains include Bacteria,
Archaea, and Eukarya.
Symbiosis - correct answer Close and often long-term interaction between two different
biological organisms.
Mutualism - correct answer Symbiotic relationship where both organisms benefit.
Commensalism - correct answer Symbiotic relationship where one organism benefits while the
other is neither helped nor harmed.
Parasitism - correct answer Symbiotic relationship where one organism (parasite) benefits at
the expense of the other (host).
Disease - correct answer Deviation from normal functioning of the body due to internal or
external dysfunctions.
Signs - correct answer Objective evidence of disease that can be observed by others (e.g.,
fever, rash).
Symptoms - correct answer Subjective evidence of disease experienced by the patient (e.g.,
pain, nausea).
Internal dysfunction - correct answer Abnormality in body function originating from within the
body.
External dysfunction - correct answer Abnormality in body function caused by external agents
like pathogens.
,Taxonomy - correct answer The science of naming, defining, and classifying organisms based
on shared characteristics.
Hierarchical classification - correct answer Organization of organisms into increasingly specific
categories.
Binomial nomenclature - correct answer The system of naming species using two terms - genus
and species.
Species - correct answer The most specific taxonomic rank; for bacteria, defined as strains with
at least 70% DNA-DNA hybridization.
Numerical taxonomy - correct answer Classification based on many observable characteristics.
DNA-DNA hybridization - correct answer Technique measuring genetic similarity between
species.
Phylogenetics - correct answer Study of evolutionary relationships among organisms.
Molecular chronometer - correct answer Molecule that changes at a relatively constant rate,
used to measure evolutionary time.
16S rRNA - correct answer Conserved gene used as a molecular chronometer for bacterial
classification.
Polyphasic approach - correct answer Using multiple techniques to classify bacteria.
Type strain - correct answer The strain that serves as the name-bearer for the species.
Convergent evolution - correct answer Independent evolution of similar traits in unrelated
lineages.
Endosymbiotic theory - correct answer Theory that mitochondria and chloroplasts originated
as free-living bacteria.
Zoonotic disease - correct answer Disease that can be transmitted from animals to humans.
Magnification - correct answer The increase in apparent size of an object.
Resolution - correct answer The ability to distinguish two adjacent points as separate.
Contrast - correct answer The difference in light intensity between an object and its
background.
Refraction - correct answer The bending of light as it passes from one medium to another.
Wavelength - correct answer The distance between two successive crests of a wave.
Empty magnification - correct answer Magnification beyond the resolving power of a
microscope.
, Negative stain - correct answer Staining technique where the background is stained but the
specimen remains unstained.
Simple stain - correct answer Using a single dye to stain cells.
Differential stain - correct answer Staining technique that distinguishes between different
types of cells or cellular components.
Gram stain - correct answer Differential staining technique classifying bacteria as Gram-
positive or Gram-negative.
Fluorescent dyes - correct answer Compounds that absorb light at one wavelength and emit
light at a longer wavelength.
GFP (Green Fluorescent Protein) - correct answer Protein that exhibits bright green
fluorescence when exposed to light.
Antigen - correct answer Molecule that triggers an immune response.
Antibody - correct answer Protein produced by the immune system that binds to a specific
antigen.
Light microscope - correct answer Microscope using visible light and lenses.
Phase contrast microscope - correct answer Microscope that converts phase shifts in light to
brightness changes to enhance contrast.
Fluorescence microscope - correct answer Microscope that illuminates specimens with specific
wavelengths and detects emitted fluorescence.
Confocal laser microscope - correct answer Microscope that uses focused laser light and a
pinhole to create detailed images of a specific plane.
Transmission electron microscope (TEM) - correct answer Microscope using electron beams to
visualize internal structures of specimens.
Scanning electron microscope (SEM) - correct answer Microscope producing 3D images of
specimens using electrons to scan the surface.
Atomic force microscope - correct answer Microscope that maps surface contours by
measuring forces between a probe and surface.
Bacillus - correct answer Rod-shaped bacterial cell.
Coccus - correct answer Spherical bacterial cell.
Vibrio - correct answer Curved rod-shaped bacterial cell.
Guide of Key Terms and Definitions for Pathogens, Immunity,
Lab Techniques, and Disease Processes
Microbiology - correct answer The scientific study of microorganisms, including bacteria,
archaea, viruses, fungi, protozoa, and algae.
Microorganisms - correct answer Living organisms that are too small to be seen by the naked
eye and require microscopy for visualization.
Prokaryote - correct answer Organism lacking a true nucleus and membrane-bound organelles;
includes bacteria and archaea.
Eukaryote - correct answer Organism with cells containing a true nucleus and membrane-
bound organelles.
Domain - correct answer Highest taxonomic rank of organisms; three domains include Bacteria,
Archaea, and Eukarya.
Symbiosis - correct answer Close and often long-term interaction between two different
biological organisms.
Mutualism - correct answer Symbiotic relationship where both organisms benefit.
Commensalism - correct answer Symbiotic relationship where one organism benefits while the
other is neither helped nor harmed.
Parasitism - correct answer Symbiotic relationship where one organism (parasite) benefits at
the expense of the other (host).
Disease - correct answer Deviation from normal functioning of the body due to internal or
external dysfunctions.
Signs - correct answer Objective evidence of disease that can be observed by others (e.g.,
fever, rash).
Symptoms - correct answer Subjective evidence of disease experienced by the patient (e.g.,
pain, nausea).
Internal dysfunction - correct answer Abnormality in body function originating from within the
body.
External dysfunction - correct answer Abnormality in body function caused by external agents
like pathogens.
,Taxonomy - correct answer The science of naming, defining, and classifying organisms based
on shared characteristics.
Hierarchical classification - correct answer Organization of organisms into increasingly specific
categories.
Binomial nomenclature - correct answer The system of naming species using two terms - genus
and species.
Species - correct answer The most specific taxonomic rank; for bacteria, defined as strains with
at least 70% DNA-DNA hybridization.
Numerical taxonomy - correct answer Classification based on many observable characteristics.
DNA-DNA hybridization - correct answer Technique measuring genetic similarity between
species.
Phylogenetics - correct answer Study of evolutionary relationships among organisms.
Molecular chronometer - correct answer Molecule that changes at a relatively constant rate,
used to measure evolutionary time.
16S rRNA - correct answer Conserved gene used as a molecular chronometer for bacterial
classification.
Polyphasic approach - correct answer Using multiple techniques to classify bacteria.
Type strain - correct answer The strain that serves as the name-bearer for the species.
Convergent evolution - correct answer Independent evolution of similar traits in unrelated
lineages.
Endosymbiotic theory - correct answer Theory that mitochondria and chloroplasts originated
as free-living bacteria.
Zoonotic disease - correct answer Disease that can be transmitted from animals to humans.
Magnification - correct answer The increase in apparent size of an object.
Resolution - correct answer The ability to distinguish two adjacent points as separate.
Contrast - correct answer The difference in light intensity between an object and its
background.
Refraction - correct answer The bending of light as it passes from one medium to another.
Wavelength - correct answer The distance between two successive crests of a wave.
Empty magnification - correct answer Magnification beyond the resolving power of a
microscope.
, Negative stain - correct answer Staining technique where the background is stained but the
specimen remains unstained.
Simple stain - correct answer Using a single dye to stain cells.
Differential stain - correct answer Staining technique that distinguishes between different
types of cells or cellular components.
Gram stain - correct answer Differential staining technique classifying bacteria as Gram-
positive or Gram-negative.
Fluorescent dyes - correct answer Compounds that absorb light at one wavelength and emit
light at a longer wavelength.
GFP (Green Fluorescent Protein) - correct answer Protein that exhibits bright green
fluorescence when exposed to light.
Antigen - correct answer Molecule that triggers an immune response.
Antibody - correct answer Protein produced by the immune system that binds to a specific
antigen.
Light microscope - correct answer Microscope using visible light and lenses.
Phase contrast microscope - correct answer Microscope that converts phase shifts in light to
brightness changes to enhance contrast.
Fluorescence microscope - correct answer Microscope that illuminates specimens with specific
wavelengths and detects emitted fluorescence.
Confocal laser microscope - correct answer Microscope that uses focused laser light and a
pinhole to create detailed images of a specific plane.
Transmission electron microscope (TEM) - correct answer Microscope using electron beams to
visualize internal structures of specimens.
Scanning electron microscope (SEM) - correct answer Microscope producing 3D images of
specimens using electrons to scan the surface.
Atomic force microscope - correct answer Microscope that maps surface contours by
measuring forces between a probe and surface.
Bacillus - correct answer Rod-shaped bacterial cell.
Coccus - correct answer Spherical bacterial cell.
Vibrio - correct answer Curved rod-shaped bacterial cell.
