Introduction to Microscopy Flashcards
The science of tissues.
Histology
Greek word for web or tissue
histos
Greek word for branch of learning
logia
This word was used to describe the different textures of body parts being dissected by an anatomist.
Tissue
Involves all aspects of tissue biology, with the focus on how cells’ structure and arrangement optimize functions specific to each organ.
Histology
In the light microscope, it focuses light rays at a specific place called the __________.
Focal point
In the light microscope, the distance between center of lens and focal point is the __________.
Focal length
The strength of lens is related to focal length.
A. True
B. False
True
Short focal length results to more magnification.
A. True
B. False
True
Types of Microscope
Light microscope
Electron microscope
Types of Light Microscope
Bright-field microscope
Dark-field microscope
Phase-contrast microscope
Fluorescence microscope
Confocal microscope
Produces a dark image against a brighter background.
A. Bright-field microscope
B. Dark-field microscope
C. Phase-contrast microscope
D. Fluorescence microscope
E. Confocal microscope
Bright-field microscope
Bright-field microscope has several objective lenses.
A. True
B. False
True
Product of the magnifications of the ocular lenses and the objective lenses.
Total magnification
Ability of a lens to separate or distinguish small objects that are close together.
Microscope resolution
The shorter the wavelength, the greater the resolution.
A. True
B. False
True
It determines the resolving power of an objective.
A. Microscope resolution
B. Numerical aperture
C. Working distance
D. Focal length
Numerical aperture
The higher the numerical aperture of the total system, the better the resolution.
A. True
B. False
True
Distance between the front surface of lens and surface of cover glass or specimen when it is sharp focus.
A. Microscope resolution
B. Numerical aperture
C. Working distance
D. Focal length
Working distance
Total magnification of the red band.
40x
Total magnification of the yellow band.
100x
Total magnification of the blue band.
400x
Total magnification of the white band.
1000x
In oil immersion, light rays that couldn’t pass through the objective lens because of reflection or refraction at the surface of the objective lens will now do so if immersion oil is used in place of air. This results in an increase in resolution and numerical aperture.
A. Both statements are true
B. Both statements are false
C. Only the first statement is true
D. Only the second statement is true
Both statements are true
The image is formed by light refracted or by specimen.
A. Bright-field microscope
B. Dark-field microscope
C. Phase-contrast microscope
D. Fluorescence microscope
E. Confocal microscope
Dark-field microscope
Produces bright image of the object against a dark background.
A. Bright-field microscope
B. Dark-field microscope
C. Phase-contrast microscope
D. Fluorescence microscope
E. Confocal microscope
Dark-field microscope
Microscope used to observe living, unstained preparations.
A. Bright-field microscope
B. Dark-field microscope
C. Phase-contrast microscope
D. Fluorescence microscope
E. Confocal microscope
Dark-field microscopy
Used to observe internal structure in eukaryotic microorganisms.
A. Bright-field microscope
B. Dark-field microscope
C. Phase-contrast microscope
D. Fluorescence microscope
E. Confocal microscope
Dark-field microscope
In using dark-field microscope, very thin histological sections can be used if unstained or only certain components are stained in silver stains.
A. True
B. False
True
Converts differences in refractive index/cell density into detected variations in light intensity.
A. Bright-field microscope
B. Dark-field microscope
C. Phase-contrast microscope
D. Fluorescence microscope
E. Confocal microscope
Phase-contrast microscope
Some light rays from hollow cone of light passing through unstained cell slowed/out of phase (dark against bright background).
A. Bright-field microscope
B. Dark-field microscope
C. Phase-contrast microscope
D. Fluorescence microscope
E. Confocal microscope
Phase-contrast microscope
Excellent way to observe living cells.
A. Bright-field microscope
B. Dark-field microscope
C. Phase-contrast microscope
D. Fluorescence microscope
E. Confocal microscope
Phase-contrast microscope
Creates image by detecting differences in refractive indices and thickness of different parts of specimen.
Differential Interference Contrast Microscope (DIC)
Which of the following best describes the use of DIC as an excellent way to observe living cells?
A. Live, unstained cells appear brightly colored and three-dimensional.
B. Cell walls, endospores, granules, vacuoles, and nuclei are clearly visible.
C. Live, stained cells appear darkly colored and three-dimensional.
D. A and B only
A and B only
Exposes specimen to ultraviolet, violet, or blue light.
A. Bright-field microscope
B. Dark-field microscope
C. Phase-contrast microscope
D. Fluorescence microscope
E. Confocal microscope
Fluorescence microscope
Stain used in fluorescence microscopy.
Fluorochromes
Shows a bright image of the object resulting from the fluorescent light emitted by the specimen
A. Bright-field microscope
B. Dark-field microscope
C. Phase-contrast microscope
D. Fluorescence microscope
E. Confocal microscope
Fluorescence microscope
It has applications in medical microbiology and microbial ecology studies.
A. Bright-field microscope
B. Dark-field microscope
C. Phase-contrast microscope
D. Fluorescence microscope
E. Confocal microscope
Fluorescence microscope
Creates sharp, composite 3D image of specimens by using laser beam, aperture to eliminate stray light, and computer interface.
A. Bright-field microscope
B. Dark-field microscope
C. Phase-contrast microscope
D. Fluorescence microscope
E. Confocal microscope
Confocal microscope
Confocal microscopy has numerous applications including study of biofilms.
A. True
B. False
True
Use beams of electrons to create highly magnified images.
A. Light microscope
B. Electron microscope
Electron microscope
Electrons replace light as the ‘illuminating’ beam.
A. Light microscope
B. Electron microscope
Electron microscope
It electron microscopy, the wavelength of electron beam is much shorter than light, resulting in much higher resolution.
A. True
B. False
True
Electrons replace light as the ‘illuminating’ beam.
A. Light microscope
B. Electron microscope
Electron microscope
In Transmission Electron Microscope (TEM), electrons scatter when they pass through thin sections of a specimen.
A. True
B. False
True
In TEM, transmitted electrons are under vacuum which reduces scatter and are used to produce clear image. Additionally, denser regions in specimen scatter more electrons and appear darker.
A. Both statements are true
B. Both statements are false
C. Only the first statement is true
D. Only the second statement is true
Both statements are true
Analogous to procedures used for light microscopy.
A. Microscope preparation
B. Specimen preparation
C. Staining preparation
D. None of the above
Specimen preparation
For transmission electron microscopy, specimens must be cut very thin.
A. True
B. False
True
Specimens are chemically fixed and stained with electron dense materials, such as heavy metals, that differentially scatter electrons.
A. True
B. False
True
Freezes specimen then fracture along longs of greatest weakness.
A. Freeze-etching
B. Staining
C. Freezing
D. Embedding
Freeze-etching
It allows for 3D observation of shapes of intracellular structures.
A. Freeze-etching
B. Staining
C. Freezing
D. Embedding
Freeze-etching
Freeze-etching reduces artifacts.
A. True
B. False
True
Uses electron excited from the surface of a specimen to create a detailed image.
A. Scanning Electron Microscope (SEM)
B. Transmission Electron Microscope (TEM)
Scanning Electron Microscope (SEM)
Produces realistic 3D image of specimen’s surface features.
A. Scanning Electron Microscope (SEM)
B. Transmission Electron Microscope (TEM)
Scanning Electron Microscope (SEM)
It can determine actual in situ location of microorganisms in ecological niches.
A. Scanning Electron Microscope (SEM)
B. Transmission Electron Microscope (TEM)
Scanning Electron Microscope (SEM)
Rapid freezing technique provides way to preserve native state of structures examined in vacuum.
A. Microscopic cryotomography
B. Electron cryotomography
Electron Cryotomography
Images are recorded from many different directions to create 3D structures.
A. Microscopic cryotomography
B. Electron cryotomography
Electron cryotomography
It provides extremely high resolution images of cytoskeletal elements, magnetosomes, inclusion bodies, flagellar motors, viral structures.
A. Microscopic cryotomography
B. Electron cryotomography
Electron cryotomography
Staining specimens help to visualize tissues.
A. True
B. False
True
The following describes the preparation and staining of specimens except:
A. Increases visibility of specimen
B. Accentuates specific morphological features
C. Preserves specimens
D. All of the above
All of the above
Preserves internal and external structures and fixes in position.
Fixation
In dehydration, organisms are usually killed and firmly attached to microscope slide.
A. True
B. False
False
Fixation that is routinely used with bacteria and archaea.
A. Heat fixation
B. Chemical fixation
C. Physical fixation
D. Biological fixation
Heat fixation
It preserves overall morphology but not internal structures.
A. Heat fixation
B. Chemical fixation
C. Physical fixation
D. Biological fixation
Heat fixation
Fixation that is used in larger and more delicate organisms.
A. Heat fixation
B. Chemical fixation
C. Physical fixation
D. Biological fixation
Chemical fixation
It protects fine cellular substructure and morphology.
A. Heat fixation
B. Chemical fixation
C. Physical fixation
D. Biological fixation
Chemical fixation
Makes internal and external structures of cell more visible by increasing contrast with background.
A. Stains
B. Dyes
Dyes
Have positively charged groups that bind to negatively charged molecules such as nucleic acids, many proteins, and the surfaces of bacterial and archaeal cells.
A. Acidic dyes
B. Basic dyes
Basic dyes
These are dyes in their ionized form that have a negative charge and bind to positively charged cell structures.
A. Acidic dyes
B. Basic dyes
Acidic dyes
Identify what kind of dye:
Methylene blue
Basic dyes
Identify what kind of dye:
Basic fuchsin
Basic dyes
Identify what kind of dye:
Crystal violet
Basic dyes
Identify what kind of dye:
Safranin
Basic dyes
Identify what kind of dye:
Malachite green
Basic dyes
Identify what kind of dye:
Eosin
Acidic dyes
Identify what kind of dye:
Rose bengal
Acidic dyes
Identify what kind of dye:
Acid fuchsin
Acidic dyes
Ionizable dyes have charged groups.
A. True
B. False
True
Basic dyes have negative charges. While the acid dyes have positive charges.
A. Both statements are true
B. Both statements are false
C. Only the first statement is true
D. Only the second statement is true
Both statements are false
A single stain is used.
A. Basic stains
B. Acidic stains
C. Neutral stains
D. Simple stains
Simple stains
Used to determine size, shape, and arrangement of bacteria.
A. Basic stains
B. Acidic stains
C. Neutral stains
D. Simple stains
Simple stains
Divides microorganisms into groups based on their staining properties.
A. Basic stains
B. Acidic stains
C. Differential staining
D. Simple stains
Differential staining
Stains used in differential staining.
Gram stain
Acid-fast stain
Stains that are used to detect presence or absence of structures.
A. Basic stains
B. Acidic stains
C. Differential stains
D. Simple stains
Differential stains
Useful for staining members of genus Mycobacterium.
A. Gram staining
B. Acid-fast staining
Acid-fast staining
Acid-fast staining is useful for staining members of genus called?
Mycobacterium
It causes tuberculosis.
Mycobacterium tuberculosis
It causes leprosy.
Mycobacterium leprae
It is responsible for their staining characteristics.
High lipid content (mycolic acid)
In gram stain, purple cells are gram positive, while red cells are gram negative. While in acid-fast stain, red cells are acid-fast, and blue cells are non-acid-fast.
A. Both statements are true
B. Both statements are false
C. Only the first statement is true
D. Only the second statement is true
Both statements are true
