MICROBIOLOGY EXAM 1,2,3 AND 4 NEWEST ACTUAL EXAM COMPLETE QUESTIONS AND CORRECT DETAILED ANSWERS (VERIFIED ANSWERS) |ALREADY GRADED A+
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MICROBIOLOGY EXAM 1 NEWEST 2024-2025 ACTUAL
EXAM COMPLETE 350 QUESTIONS AND CORRECT
DETAILED ANSWERS (VERIFIED ANSWERS)
|ALREADY GRADED A+
All of the following are associated with filtration EXCEPT:
A) nitrocellulose or plastic membrane filters.
B) varying thicknesses of membrane filters used.
C) HEPA filters are used to filter air.
D) viruses and proteins can be trapped by some filters.
E) sterilization of heat-sensitive materials. – ANSWER- B) varying
thicknesses of membrane filters used.
Describe some factors that can either increase or decrease the
effectiveness of antimicrobial agents. – ANSWER- duration of exposure-
->in general, longer/increased exposure time, increases efficiency of the
agent
concentration of the agent–>in general increase concentration of agent
increases efficiency…however saturable once agent reaches max kill,
rate increases, does not drop efficiency.
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presence of organic debris–>debris may be food, feces, blood, vomit,
skin, hair, etc. it also blocks agent from receiving microbes: may need to
pre clean. in general increased debris decreases efficiency.
surface features–>in general rougher/more porous surface, decreases
efficiency. ideally wants agent with low surface tension.
*water has high tension surface
*tension goes in to cracks/pores
temperature–>in general a temperature increases efficiency. usually
increased temperature reduces time required to clean and reduces
concentration level.
*less to do with agent
*more to do with microbe
population size(how many microbes are present)–>in general larger
population/more microbes present, decreases efficiency. most agents
have a defined kill rate. the larger the population the more time to kill
eg.. agent–>50% per minute kill rate(pop. a. 100-50-25-12-6-3-1-0) 1
minute to kill
population composition–>in general, more diverse/mixed population,
decrease efficiency. population may be diverse in many different groups
of microbes present, presence of endospore forming species, age of
cells(older/mature cells more difficult to kill)
eg.. pop. b. (1000-500-250-125-62-31-16-8-4-2-1-0) 11 minutes to kill
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The spores of which of the following microbes are the most resistant to
every known sterilization technique? – ANSWER- Bacillus
stearothermophilus
Match the pioneer(s) in microbiology with their accomplishment(s).
Fleming
Snow
Jenner
Ehrlich
Watson & Crick – ANSWER- idk
Fleming- immunologist and discovered lysosome and penicillin
Snow- epidemiology and infection control (emerging infectious disease)
Jenner- Immunology (Developed smallpox immunization)
Ehrlich – chemotherapy
Watson & Crick – discovered DNA molecule
Compare and contrast the three domains identifies by Woese-Eukarya,
Bacteria, and Archaea. – ANSWER- written
A bacterial capsule
A. is generally composed of polysaccharide
B. facilitates nonspecific adherence
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C. is antiphagocytic
D. is external to the cell wall
E. all of the above – ANSWER- E. all of the above
A bacterial cell that is moving away from a toxic pollutant in the
environment during the daylight is said to exhibit – ANSWER- negative
chemotaxis
If a microbiology lab technician left the safranin out of the Gram stain
procedure, what would be the result? – ANSWER- Gram-positive cells
would be purple, and Gram negative cells would be colorless.
The number of bacteria resulting from the growth of one bacterium
through five generations: – ANSWER- idk
Which of the following quantification techniques can distinguish
between living and dead cells in a culture?
A) microscopic counts
B) dry weight
C) metabolic activity
D) a Coulter counter
E) turbidity – ANSWER- C) metabolic activity
A cell that uses an organic carbon source and obtains energy from a light
would be called a
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MICROBIOLOGY EXAM 2 NEWEST 2024-2025 ACTUAL
EXAM COMPLETE 350 QUESTIONS AND CORRECT
DETAILED ANSWERS (VERIFIED ANSWERS)
|ALREADY GRADED A+
Which statement is NOT an aim in the use of drugs in antimicrobial
chemotherapy?
a. have selective toxicity
b. be active even in high dilutions
c. be broken down and excreted rapidly
d. be microbicidal – ANSWER- c. be broken down and excreted rapidly
Drugs that prevent the formation of the bacterial cell wall are
a. quinolones
b. beta-lactams
c. tetracyclines
d. aminoglycosides – ANSWER- b. beta-lactams
Microbial resistance to drugs is acquired through
a. conjugation
b. transformation
c. transduction
d. all of these – ANSWER- d. all of these
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R factors are _ that contains a code for _
a. genes, replication
b. plasmids, drug resistance
c. transposons, interferon
d. plasmids, conjugation – ANSWER- b. plasmids, drug resistance
Phage therapy is a technique that uses
a. chemicals to destroy phages infecting human cells
b. chemicals to foster the growth of beneficial phages in the body
c. phages to foster the growth of beneficial phages in the body
d. phages to target pathogenic bacteria in the body – ANSWER- d.
phages to target pathogenic bacteria in the body
Most antihelminthic drugs function by
a. weakening the worms so they can be flushed out by the intestine
b. inhibiting worm metabolism
c. blocking the absorption of nutrients
d. inhibiting egg production – ANSWER- b. inhibiting worm metabolism
Which of the following modes of action would be most selectively
toxic?
a. interrupting ribosomal function
b. dissolving the cell membrane
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c. preventing cell wall synthesis
d. inhibiting DNA replication – ANSWER- c. preventing cell wall
synthesis
The MIC is the of a drug that is required to inhibit growth of a
microbe.
a. largest concentration
b. standard dose
c. smallest concentration
d. lowest dilution – ANSWER- c. smallest concentration
An antimicrobial drug with a _ therapeutic index is a better choice than one with a __ therapeutic index.
a. low, high
b. high, low – ANSWER- b. high, low
True or false? Most antiviral agents work by destroying active viruses –
ANSWER- False. Most antiviral agents work by blocking an essential
viral activity
True or false? Sulfonamide drugs work by disrupting protein synthesis –
ANSWER- False. Sulfonamide drugs work by disrupting folic acid
synthesis
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True or false? Biofilms are difficult to treat and don’t always respond to
antibiotics – ANSWER- True
True or false? An antibiotic that disrupts the host’s normal biota can
cause a superinfection – ANSWER- True
True or false? Drug resistance can occur when a patient’s immune
system becomes reactive to a drug – ANSWER- False. Drug resistance
can occur when a bacterium stops being susceptible to an antibiotic
A critically ill patient enters your emergency room, exhibiting signs and
symptoms of severe septic shock. In this case, should you immediately
begin treatment with a broad-spectrum drug or a narrow-spectrum drug?
Explain your answer and discuss any possible consequences of using
either drug in the patient. – ANSWER- Broad spectrum since the source
is unknown, the larger the scale the more likely the drug is to help.
Consequences of narrow would be that the bacteria it targets is not the
one affecting patient and with broad, the patient has greater risk of
developing resistance to drugs used
A friend was recently diagnosed with strep throat. One week after his
treatment, he redeveloped the infection. In conversation, your friend tells
you, “I must have become immune to the drug the doctor gave me!”
a. Discuss the validity of your friend’s statement, providing evidence in
support of or refuting his claim. – ANSWER- He himself cannot become
immune to the drug, instead the bacteria is no longer susceptible to the
drug.
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MICROBIOLOGY EXAM 3 NEWEST 2024-2025 ACTUAL
EXAM COMPLETE 300 QUESTIONS AND CORRECT
DETAILED ANSWERS (VERIFIED ANSWERS)
|ALREADY GRADED A+
Which molecule provides the template that is directly used to make a
protein in translation
a. tRNA
b mRNA
c. the gene
d. DNA – ANSWER- b. mRNA
A bacteriophage (phage) infects
a. bacteria
b. mammals
c. only humans
d. arthropods
e. any eukaryote – ANSWER- a. bacteria
Which microorganism commonly produces endospores
a. Enterobacter
b. Proteus
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c. Escherichis
d. Clostridium – ANSWER- d. Clostridium
Which type of RNA is used to make ribosomes
a. DNA
b. rRNA
c. mRNA
d. tRNA – ANSWER- b. rRNA
Proglottids are
a. viral structures
b. prokaryotic structures
c. reproductive structure in tapeworms
d. none of the above – ANSWER- c. reproductive structures in
tapeworms
What is the final product of translation
a. mRNA
b. proteins
c. amino acids
d. DNA
e. none of the above – ANSWER- b. proteins
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What carries the amino acid to the correct spot on an mRNA molecule
a. Ribosomes
b. proteins
c. tRNA
d. codons – ANSWER- c. tRNA
In the inducible lac-operon, when lactose is not present the operon is
a. off, with no transcription occurring
b. on, with transcription occurring
c. neither, the presence of absence of lactose is not relevant – ANSWERa. off, with no transcription occurring
Which genus of bacteria causes diarrhea with massive water and
electrolyte loss and is transmitted through fecal contaminated water
a. Bacillus
b. Clostridium
c. Escherichia
d. Vibrio
e. Proteus – ANSWER- d. Vibrio
Which of the following is not a trait shared by both prokaryotic domains
a. all are unicellular
b. all have a plasma membrane
c. both domains have organisms that can undergo methanogenesis
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d. both domains have anaerobic and aerobic representatives – ANSWERc. both domains have organisms the can undergo methanogenesis
Which of the following is acellular
a. fungi
b. protozoans
c. algae
d. bacteria
e. viruses – ANSWER- e. viruses
Place the following steps in a lytic infection in the correct order. 1-
penetration, 2-release, 3-assembly, 4-attachment, 5-biosynthesis
a. 1,2,3,4,5
b. 4,1,5,3,2
c. 4,1,3,5,2
d. 4,5,1,2,3 – ANSWER- b. 4,1,5,3,2
Which statement about Plasmodium is not correct
a. it is transmitted by a mosquito
b. it is endemic to over 100 countries
c. it is an obligate intracellular parasite
d. it causes Q fever – ANSWER- d. it causes Q fever
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MICROBIOLOGY EXAM 4 NEWEST 2024-2025 ACTUAL
EXAM COMPLETE 220 QUESTIONS AND CORRECT
DETAILED ANSWERS (VERIFIED ANSWERS)
|ALREADY GRADED A+
Match the microbial growth control term with its correct definition:
a technique used to prevent contamination to maintain sterility
A. antisepsis
B. asepsis
C. disinfection
D. pasteurization
E. sanitization – ANSWER- B
Match the microbial growth control term with its correct definition:
a chemical process used to control microbial growth on inanimate
objects
A. antisepsis
B. asepsis
C. disinfection
D. pasteurization
E. sanitization – ANSWER- C
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Match the microbial growth control term with its correct definition:
a process that kills non-spore forming pathogenic pathogens
A. antisepsis
B. asepsis
C. disinfection
D. pasteurization
E. sanitization – ANSWER- D
Match the microbial growth control term with its correct definition:
lowering microbial load to public health standards
A. antisepsis
B. asepsis
C. disinfection
D. pasteurization
E. sanitization – ANSWER- E
Microbial control methods that kill _ are able to sterilize.
A. viruses
B. Bacillus
C. endospores
D. cysts
E. none of the above – ANSWER- C
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Microbial resistance to drugs is acquired through __.
A. conjugation
B. transformation
C. transduction
D. all of these – ANSWER- D
Most antihelminthic drugs function by?
A. weakening (various ways) so they can then be flushed out of the
intestines
B. blocking the absorption of nutrients
C. inhibiting egg production
D. breaking down the cell wall – ANSWER- A
Reverse transcriptase inhibitors, such as AZT, can be used to target
which virus?
A. herpes
B. HIV
C. influenza
D. rabies – ANSWER- B
Silver nitrate is used?
A. in eye drops for newborns
B. as a mouthwash
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C. to treat gonorrhea
D. to disinfect water – ANSWER- A
Sulfonamide drugs initially disrupt which process?
A. folic acid synthesis
B. transcriptions
C. PABA synthesis
D. protein synthesis – ANSWER- A
The MIC is the __ of a drug that is required to inhibit growth of a
microbe.
A. largest concentration
B. standard dose
C. smallest concentration
D. lowest dilution – ANSWER- C
The aminoglycosides directly target which structure of the bacterial cell?
A. 30S ribosomal subunit
B. 50S ribosomal subunit
C. cell wall
D. plasma membrane – ANSWER- A
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