Prescott's Microbiology Exam 1 Study Guide LRC
What is the definition of microbiology? - (correct Answer) - Microbiology is a branch off biology that
deals with microorganisms.
Virology - (correct Answer) - This is the study that focuses on acellular accepts of viruses.
Mycology - (correct Answer) - The study of fungi.
Phycology - (correct Answer) - The study of algae.
Protozoology - (correct Answer) - The study of protozoans.
What did Pasteur do to disprove the theory of spontaneous generation? - (correct Answer) - - 1861, used
curved long-neck flask to prevent microbes from falling into nutrient liquid and when no growth
occurred disproved spontaneous generation
- Presented the law of biogenesis: "Ommevivum ex vivo", life only comes from life.
How does a bright field microscope work? - (correct Answer) - The field around object is bright. The
object is dark; Chromophores (pigments) absorb and reflects color light.
How does a dark field microscope work? - (correct Answer) - The dark field microscope uses a small
opaque light stop that blocks most of the light from the illuminator as it passed through the condenser.
Typically shows bright object and dark background.
How are specimens prepared for light microscopy and why use oil immersion? - (correct Answer) - -
Specimen are prepared with wet mounts: where the specimen is placed in a drop of liquid.
- Using oil immersion increases the resolving power of a microscope.
What is fixation and why is it generally done? - (correct Answer) - Fixation refers to the process of
attaching cells to a slide (Preservation). Often created from heating (Bacteria/ archea) or chemically
(protozoan) treating the specimen. Fixation also kills microorganisms in the specimen, stopping their
movement and metabolism while preserving the integrity of their cellular components for observation
Basic dyes vs Acidic dyes - (correct Answer) - - If the chromophore is positively charged ion, the stain is
classified as basic dye.
- If the chromophore is negatively charge ion, the stain is considered acidic dye.
What is a fluorescent microscopy? - (correct Answer) - - focuses with the use of fluorochromes, capable
of absorbing energy from light source and then emitting this energy as visible light.
, - Uses excitation light, EMR with short wavelength towards specimen. The specimen emits visible light
with greater wavelengths.
What is special about confocal microscopy? - (correct Answer) - Uses a laser to scan multiple z-planes.
Produces numerous 2D, high-resolution images at various depths. Constructed into 3D image by
computer.
How does electron microscopy work? - (correct Answer) - Uses short-wavelength electron beams rather
than light to increase magnification and resolution.
What are the two types of electron microscope and how are their samples prepared? - (correct Answer)
- - The two electron microscope types are TEM (transmission electron microscope) and SEM (scanning
electron microscope).
- For TEM, specimen must be extremely thin. The opactiy can be enhanced by staining speciment with
heavy metals (electron dense).
- For SEM, specimens are dried and prepared with fixatives that reduces artifacts such as shriveling, that
can be produce by drying. Sputter-coated with thin layer of metal (gold).
What distinguishes a prokaryotic cell from a eukaryotic? - (correct Answer) - - Prokaryotic cells have no
membrane bound organelles. No nucleus. Unicellular
- Eukaryotic cells multicellular and membrane bound organelles.
Where is the genome in a prokaryotic cell and what is it like? - (correct Answer) - Within the nucleoid. It
is contained in a single circular DNA molecule.
Common bacterial shapes - (correct Answer) - - Cocci: round
- Bacilli: Rods
- Streptococci: chains of cocci
- Staphylococci: Grape-like
What is glycocalyx, its role and composition? - (correct Answer) - Glycocalyx is like a slime on the outside
of a bacterial cell. This allows them to resist engulfment of white blood cells and protozoans. Composed
What is the definition of microbiology? - (correct Answer) - Microbiology is a branch off biology that
deals with microorganisms.
Virology - (correct Answer) - This is the study that focuses on acellular accepts of viruses.
Mycology - (correct Answer) - The study of fungi.
Phycology - (correct Answer) - The study of algae.
Protozoology - (correct Answer) - The study of protozoans.
What did Pasteur do to disprove the theory of spontaneous generation? - (correct Answer) - - 1861, used
curved long-neck flask to prevent microbes from falling into nutrient liquid and when no growth
occurred disproved spontaneous generation
- Presented the law of biogenesis: "Ommevivum ex vivo", life only comes from life.
How does a bright field microscope work? - (correct Answer) - The field around object is bright. The
object is dark; Chromophores (pigments) absorb and reflects color light.
How does a dark field microscope work? - (correct Answer) - The dark field microscope uses a small
opaque light stop that blocks most of the light from the illuminator as it passed through the condenser.
Typically shows bright object and dark background.
How are specimens prepared for light microscopy and why use oil immersion? - (correct Answer) - -
Specimen are prepared with wet mounts: where the specimen is placed in a drop of liquid.
- Using oil immersion increases the resolving power of a microscope.
What is fixation and why is it generally done? - (correct Answer) - Fixation refers to the process of
attaching cells to a slide (Preservation). Often created from heating (Bacteria/ archea) or chemically
(protozoan) treating the specimen. Fixation also kills microorganisms in the specimen, stopping their
movement and metabolism while preserving the integrity of their cellular components for observation
Basic dyes vs Acidic dyes - (correct Answer) - - If the chromophore is positively charged ion, the stain is
classified as basic dye.
- If the chromophore is negatively charge ion, the stain is considered acidic dye.
What is a fluorescent microscopy? - (correct Answer) - - focuses with the use of fluorochromes, capable
of absorbing energy from light source and then emitting this energy as visible light.
, - Uses excitation light, EMR with short wavelength towards specimen. The specimen emits visible light
with greater wavelengths.
What is special about confocal microscopy? - (correct Answer) - Uses a laser to scan multiple z-planes.
Produces numerous 2D, high-resolution images at various depths. Constructed into 3D image by
computer.
How does electron microscopy work? - (correct Answer) - Uses short-wavelength electron beams rather
than light to increase magnification and resolution.
What are the two types of electron microscope and how are their samples prepared? - (correct Answer)
- - The two electron microscope types are TEM (transmission electron microscope) and SEM (scanning
electron microscope).
- For TEM, specimen must be extremely thin. The opactiy can be enhanced by staining speciment with
heavy metals (electron dense).
- For SEM, specimens are dried and prepared with fixatives that reduces artifacts such as shriveling, that
can be produce by drying. Sputter-coated with thin layer of metal (gold).
What distinguishes a prokaryotic cell from a eukaryotic? - (correct Answer) - - Prokaryotic cells have no
membrane bound organelles. No nucleus. Unicellular
- Eukaryotic cells multicellular and membrane bound organelles.
Where is the genome in a prokaryotic cell and what is it like? - (correct Answer) - Within the nucleoid. It
is contained in a single circular DNA molecule.
Common bacterial shapes - (correct Answer) - - Cocci: round
- Bacilli: Rods
- Streptococci: chains of cocci
- Staphylococci: Grape-like
What is glycocalyx, its role and composition? - (correct Answer) - Glycocalyx is like a slime on the outside
of a bacterial cell. This allows them to resist engulfment of white blood cells and protozoans. Composed
