MICR 2420: Final Exam Questions with
Complete Solutions 2025-2026
Updated.
Wet mount - Answer A slide preparation technique where a specimen is placed on the slide
with a drop of liquid
Darkfield microscopy - Answer Type of microscopy where a bright image is seen on a dark
background
Brightfield microscopy - Answer Type of microscopy where a dark image is seen on a bright
background
Phase contrast microscopy - Answer Type of microscopy where higher contrast and higher-
definition images are produced
Gram stain - Answer A differential staining technique that distinguishes bacteria based upon
their cell wall structure
Acid fast stain - Answer A differential staining technique that differentiates cells that have
mycolic acids in their gram-positive cell walls
Endospore stain - Answer A differential staining technique that uses two stains to make
bacterial endospores appear distinct from the rest of the cell
Capsule stain - Answer A negative staining technique that stains around a bacterial capsule
while leaving the capsule clear
Scanning electron microscope - Answer A type of EM that forms an image of the cell surface
and topography
Transmission electron microscope - Answer A type of EM that focuses on a thinly spliced
specimen
Fluorescence microscope - Answer A microscope that uses natural fluorochromes or
fluorescent stains to increase contrast
, Algae - Answer Unicellular or multicellular eukaryotic photosynthetic organisms, lack
vascular tissues and organs
Prokaryote - Answer An organism whose cell structure does not include a membrane-bound
nucleus
Eukaryote - Answer An organism made up of one or more cells that contain a membrane-
bound nucleus and organelles
Endosymbiotic theory - Answer The theory that mitochondria and chloroplasts arose as a
result of prokaryotic cells establishing a symbiotic relationship within a eukaryotic host
Cyanobacteria - Answer Phototrophic, chlorphyll-containing bacteria that produce large
amounts of gaseous oxygen
Plasmid - Answer Small, circular DNA molecule that is independent from the bacterial
chromosome
Plasma membrane - Answer Lipid bilayer with embedded proteins that defines the boundary
of a cell
Proton motive force - Answer Electrochemical gradient formed by the accumulation of
protons on one side of the membrane
Bacteriorhodopsin - Answer A protein present in the bacterium genus Halobacterium, it
transports protons across the cytoplasmic membrane when illuminated
Photosynthesis - Answer A process where phototrophic organisms convert solar energy into
chemical energy
Phototroph - Answer An organism that obtains its energy from light
Lithotroph - Answer An organism that uses inorganic chemicals as its electron source
Autotroph - Answer An organism that converts its inorganic carbon dioxide into organic
carbon
Heterotroph - Answer An organism that uses fixed organic carbon compounds as its carbon
source
Complete Solutions 2025-2026
Updated.
Wet mount - Answer A slide preparation technique where a specimen is placed on the slide
with a drop of liquid
Darkfield microscopy - Answer Type of microscopy where a bright image is seen on a dark
background
Brightfield microscopy - Answer Type of microscopy where a dark image is seen on a bright
background
Phase contrast microscopy - Answer Type of microscopy where higher contrast and higher-
definition images are produced
Gram stain - Answer A differential staining technique that distinguishes bacteria based upon
their cell wall structure
Acid fast stain - Answer A differential staining technique that differentiates cells that have
mycolic acids in their gram-positive cell walls
Endospore stain - Answer A differential staining technique that uses two stains to make
bacterial endospores appear distinct from the rest of the cell
Capsule stain - Answer A negative staining technique that stains around a bacterial capsule
while leaving the capsule clear
Scanning electron microscope - Answer A type of EM that forms an image of the cell surface
and topography
Transmission electron microscope - Answer A type of EM that focuses on a thinly spliced
specimen
Fluorescence microscope - Answer A microscope that uses natural fluorochromes or
fluorescent stains to increase contrast
, Algae - Answer Unicellular or multicellular eukaryotic photosynthetic organisms, lack
vascular tissues and organs
Prokaryote - Answer An organism whose cell structure does not include a membrane-bound
nucleus
Eukaryote - Answer An organism made up of one or more cells that contain a membrane-
bound nucleus and organelles
Endosymbiotic theory - Answer The theory that mitochondria and chloroplasts arose as a
result of prokaryotic cells establishing a symbiotic relationship within a eukaryotic host
Cyanobacteria - Answer Phototrophic, chlorphyll-containing bacteria that produce large
amounts of gaseous oxygen
Plasmid - Answer Small, circular DNA molecule that is independent from the bacterial
chromosome
Plasma membrane - Answer Lipid bilayer with embedded proteins that defines the boundary
of a cell
Proton motive force - Answer Electrochemical gradient formed by the accumulation of
protons on one side of the membrane
Bacteriorhodopsin - Answer A protein present in the bacterium genus Halobacterium, it
transports protons across the cytoplasmic membrane when illuminated
Photosynthesis - Answer A process where phototrophic organisms convert solar energy into
chemical energy
Phototroph - Answer An organism that obtains its energy from light
Lithotroph - Answer An organism that uses inorganic chemicals as its electron source
Autotroph - Answer An organism that converts its inorganic carbon dioxide into organic
carbon
Heterotroph - Answer An organism that uses fixed organic carbon compounds as its carbon
source
