Download Lecture Exam 1

Exam 1 Study Guide
Note: These learning objectives are intended as a study guide. This is not intended to be the sole source of your studies. This
is not necessarily a complete guide and you should be familiar with all topics covered in lecture as well as Independent Study.
Focus topics will form the basis of the short answer and essay questions on exams.
CHAPTER 1
- Know introductory material on the ways microbiology has contributed to the understanding of infectious disease,
biotechnology, environmental science, and human health
- Describe to contribution of the following to science and microbiology:
Anton van Leeuwenhoek
Robert Hooke
Edward Jenner
Louis Pasteur
Paul Ehrlich
Robert Koch
Alexander Flemming
Joseph Lister
Francesco Redi
- Describe the difference between spontaneous generation and biogenesis
- Explain the significance of the criteria called Koch's Postulates
- Define and give an example of the binomial nomenclature system in proper scientific format
- List the three domains of life and know which kingdoms belong to each domain
-The Center for Disease Control (CDC) and other world health organizations are intensely focused on EIDs and re-EIDs.
Describe three different factors that are responsible for the recent increase in EIDs (or re-EIDs) and give microbial examples
of each. Which factor do you think will be the biggest contributor to EIDs in the future?
CHAPTER 3
Define the following and be able to convert from one unit to another:
meter (m)
centimeter (cm)
millimeter (mm)
micrometer (µm)
nanometer (nm)
Be able to identify and give the function of the following components of a light microscope:
ocular lens
light source
coarse adjustment
objective lens
condenser
fine adjustment
stage
iris-diaphragm
arm
Define resolving power
Determine the total magnification of a light microscope for different objective lenses
Describe basic characteristics, including most beneficial use, of the following types of microscopy:
brightfield
darkfield
phase-contrast
fluorescence
transmission electron
scanning electron
Define the following:
staining
heat fixation
basic dye
acidic dye
simple stains
differential stains
special stains
mordant
decolorization
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Be able to differentiate between Gram (+) and Gram (-) bacteria, both in their stain color and why they stain
differently:
To observe specimens under the scope, often times one must rely on staining. One of the most influential and crucial
stains might well be the Gram stain. Know the following about the Gram stain:
- Steps used to prepare a slide for staining (smear, air dry, heat fix)
- Steps used in the Gram stain itself, along with reagents used, including the appearance of cells at each step
- Why the Gram stain is a differential stain and not a simple stain
- How cell wall composition results in the differential staining results (see Focus Topic #1 in Chapter 4)
CHAPTER 4
List 4 differences between prokaryotic and eukaryotic cells, and define the terms prokaryotic and eukaryotic.
Define the following:
coccus
bacillus
spirillum
vibrio
diplo- strepto- staphylopleomorphic
Describe the structure and function of the following prokaryotic structures:
capsule (glycocalyx)
flagella
sex pili
attachment pili
axial filaments
ribosomes
Compare the chemical components of the cell walls of Gram + versus Gram Describe why the cell wall composition contributes to the results of Gram staining
Describe what aspects of the Gram – and Gram + cell walls contribute to pathogenicity
Define the following:
osmotic lysis
diffusion
osmosis
osmotic pressure
semipermeable membrane
concentration gradient
Describe the purpose and circumstances for endospore formation, including the processes of sporulation and
germination.
FOCUS TOPICS:
1. Within the prokaryotes, the cell wall plays a crucial role in both determining the properties of the microbe, as well
as the way in which humans attempt to control them. You should know the components of the prokaryotic cell wall
and the differences between a Gram positive and Gram negative wall.
2. Based on the properties of prokaryotic cells, provide evidence supporting the endosymbiotic theory.
CHAPTER 6
Be able to define what "growth" refers to in microbiology.
Be able to explain how the following factors affect growth:
temperature
pH
osmotic pressure
Explain the difference in temperature requirements of the following groups of bacteria:
psychrophiles
psychrotrophs
mesophiles
thermophiles
Know the difference between osmotic pressure requirements for:
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non-halophiles
extreme halophiles
moderate halophiles
Know the chemical requirements for growth (macro- and micro- elements) and how different organisms acquire
these chemicals
Describe the significance/ function of the following forms of oxygen and important enzymes:
superoxide free radicals
superoxide dismutase
peroxide anion
catalase
peroxidase
Differentiate, on the basis of oxygen tolerance and metabolism, of the following groups of bacteria:
obligate aerobes
facultative anaerobes
obligate anaerobes
aerotolerant anaerobes
microaerophiles
Describe the following types of culture media and know the examples given in class:
chemically defined
complex
selective
differential
Describe how a streak plate is used to isolate pure cultures from a mixed culture
Recognize and describe the phases of a typical bacterial growth curve: Lag phase, Log phase, Stationary phase, and
Death phase.
Explain general process and advantages of the following methods of measurement of microbial growth:
direct microscopic count
serial dilution and standard plate count
filtration
most probable number
turbidity
Oxygen is a key chemical involved in both metabolic pathways and the growth and survival of microbial cells.
Understand and be able to describe the enzymes and metabolic pathways used by obligate aerobes, facultative
anaerobes, obligate anaerobes, and aerotolerant anaerobes.
Proper media is essential for working in a microbiology lab, or for culturing pathogenic microbes in a medical
environment. You should understand the different types of media used in the laboratory setting (i.e. selective,
differential, complex, etc.), know examples of each, and be able to use this information to answer questions such
as:
a. What media you would use to isolate Gram negative from a Gram positive bacteria and why?
b. What media would you use to identify E. coli from a stool sample and why?
c. What media would show if Staphylococcus aureus is present in a nasal swab from a patient and
why?
CHAPTER 7
Define the following terms of bacterial destruction and suppression:
sterilization
disinfection
antisepsis
degermation
sanitization
bacteriostatic
bacteriocidial
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Be familiar with mechanism of action for:
PHYSICAL METHODS:
boiling
dry heat
autoclaving
pasteurization
CHEMICAL METHODS:
biguanides
alcohols
halogens
osmotic pressure
nonionizing radiation
surfactants
organic acids
aldehydes
Given the options of chemical growth control methods shown above, identify which one/s would be
optimal for use against a:
a.
b.
c.
d.
Spore forming organism
Gram-negative bacteria
Mycobacterium
Virus
Be able to support your answer using mechanisms of action (note: there might be more than one
chemical that would work. It is sufficient to identify ONE and provide mechanism of action)
CHAPTER 8/9
Define the term biofilm and give examples of where you would find them in nature, medicine, and industry.
Describe 5 advantages of biofilm formation for a microbe.
Define the following terms:
genetics
genomics
chromosome
gene
genetic code
genetic recombination
phenotype
genotype
intron
exon
Describe the structure and base pairing of DNA.
Know the process of DNA replication in bacteria, including key enzymes (See Figure 8.6).
Know the process of transcription, including key enzymes (see Figure 8.7)
Transcribe and translate from a strand of DNA
Recognize the following mutations and examples given in class:
missense mutation
nonsense mutation
silent mutation
frameshift mutation
Describe the following mutagens and know examples of each:
nucleoside analogs
alkylating agents
deaminating agents
radiation
Explain how a gene may be repressed or induced. Use terminology that includes the following:
promoter
operon
inducer
structural genes
regulatory gene
co-repressor
operator
repressor protein
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Describe the lac operon model of E. coli for the lactose operon.
Describe Griffith's experiment demonstrating genetic transformation.
Describe conjugation in bacteria using the following key terms:
F+ cell
F- cell
plasmid
Hfr cell
Describe the different between a temperate (lysogenic) and virulent (lytic) phage and how it results in generalized or
specialized transduction
Describe the following:
F plasmids
Resistance plasmids
Virulence plasmids
Operons are gene arrangements unique to prokaryotic organisms. Be able to define an operon, including the roles of
promoters, repressors, operators, structural genes and regulatory genes. Explain how these genes and proteins work
together to induce expression of a particular gene. Give an example.
There are several gene transfer methods unique to bacteria that have been harnessed for our own use for genetic
recombination in the biotechnology and laboratory environment. Describe these gene transfer methods:
transformation, transduction, and conjugation. Be sure to include the type/ source of DNA transferred, the mediator of
DNA transfer (if any) and any additional requirements. In what situations are these methods useful in the lab?
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