Microbiology chapters 6-9

Which of the following is an organic growth factor?
A) Glucose
B) NAD+ and Vitamin B1
C) Peptone
D) NH4H2PO4
E) H2O

B) NAD+ and Vitamin B1

Which of the following is an example of a metabolic activity that could be used to measure microbial growth?
A) Standard plate count
B) Glucose consumption
C) Direct microscopic count
D) Turbidity
E) MPN

B) Glucose consumption

In one hospital, Pseudomonas aeruginosa serotype 10 infected the biliary tract of 10% of 1300 patients who underwent gastrointestinal endoscopic procedures. After each use, endoscopes were washed with an automatic reprocessor that flushed detergent and glutaraldehyde through the endoscopes, followed by a tap water rinse. P. aeruginosa 10 was not isolated from the detergent, glutaraldehyde, or tap water. What was the source of the infections?
A) Bacterial cell walls in the water
B) A biofilm in the reprocessor
C) Contaminated disinfectant
D) Fecal contamination of the bile ducts

B) A biofilm in the reprocessor

Patients with indwelling catheters are susceptible to infections because
A) Injected solutions are contaminated.
B) Their immune systems are weakened.
C) Infections can be transmitted from other people.
D) Biofilms develop on catheters.
E) Bacteria cause infections.

D. Biofilms develop on catheters

If cells are grown in media containing amino acids labeled with radioactive nitrogen (15N), most of 6) radioactivity will be found in the cells’
A) DNA.
B) proteins.
C) phospholipids.
D) DNA and proteins.
E) DNA and phospholipids.

D) DNA and proteins.

Which of the following elements is NOT correctly matched with its cellular function?

A) sulfur — used for synthesis of thiamin and biotin
B) phosphorus — incorporated into nucleic acids
C) magnesium and potassium — required as cofactors for enzymes
D) nitrogen — needed for amino acid synthesis
E) None of the answers is correct; all of the elements are correctly matched.

E) None of the answers is correct; all of the elements are correctly matched.

Pathogenic bacteria isolated from the respiratory or intestinal tracts of humans are
A) strict aerobes that grow best in reducing media.
B) facultative anaerobes that require reducing media for growth.
C) strict aerobes that grow best in candle jars.
D) capnophiles that grow best in carbon dioxide incubators.
E) capnophiles that prefer highly oxygenated growth conditions.

D) capnophiles that grow best in carbon dioxide incubators.

The biosafety level (BSL) for most introductory microbiology laboratories is
A) BSL-1.
B) BSL-2.
C) BSL-3.
D) BSL-4.

A) BSL-1.

The biosafety level (BSL) for a clinical microbiology laboratory working with potentially airborne pathogens, such as tuberculosis bacteria, is
A) BSL-1.
B) BSL-2.
C) BSL-3.
D) BSL-4.

C) BSL-3.

A sample of milk is tested for its bacterial content in a plate count assay. A one-milliliter sample of the milk is diluted in a 1:10 dilution series. One milliliter of the third dilution tube is plated in a pour plate. After incubation, the plate has 54 colonies, indicating that the original milk sample contained

A) 54 cells.

B) 540 cells.

C) 5400 cells.

D) 54,000 cells.

E) 540,000 cells.

D) 54,000 cells.

Which of the following is an example of a metabolic activity that could be used to measure microbial growth?

A) glucose consumption
B) standard plate count
C) MPN
D) direct microscopic count
E) turbidity

A) glucose consumption

Which of the following is the best method to sterilize heat-labile solutions?

A) pasteurization
B) membrane filtration
C) freezing
D) autoclave
E) dry heat

B) membrane filtration

Which of the following best describes the pattern of microbial death?

A) All the cells in a culture die at once.
B) The pattern varies depending on the antimicrobial agent.
C) Not all of the cells in a culture are killed.
D) The cells in a population die at a constant rate.
E) The pattern varies depending on the species.

D) The cells in a population die at a constant rate.

Which of the following chemical agents is used for sterilization?

A) chlorine
B) ethylene oxide
C) soap
D) alcohol
E) phenolics

B) ethylene oxide

Which of the following substances is used for surgical hand scrubs?

A) chlorine bleach
B) soap
C) chlorhexidine
D) phenol
E) glutaraldehyde

C) chlorhexidine

Which of the following pairs of terms is mismatched?

A) bacteriostatic — kills vegetative bacterial cells
B) germicide – kills microbes
C) virucide – inactivates viruses
D) fungicide — kills yeasts and molds
E) sterilant — destroys all living microorganisms

A) bacteriostatic — kills vegetative bacterial cells

The antimicrobial activity of chlorine is due to which of the following?

A) the formation of hypochlorous acid
B) the formation of ozone
C) disruption of the plasma membrane
D) the formation of hydrochloric acid
E) the formation of a hypochlorite ion

A) the formation of hypochlorous acid

Which of the following regarding antimicrobial control agents is FALSE?

A) Contaminating organic debris such as blood or sputum decrease effectiveness.
B) Some agents inactivate viruses by attacking cell membrane lipids.
C) Some agents kill by denaturing microbial cell proteins
D) Silver is used for treating antibiotic-resistant bacteria.
E) Some agents affect microbial cell membranes by dissolving lipids.

B) Some agents inactivate viruses by attacking cell membrane lipids.

Which of the following does NOT achieve sterilization?

A) pasteurization
B) ethylene oxide
C) supercritical fluids
D) dry heat
E) autoclave

A) pasteurization

Which of the following is a limitation of the autoclave?

A) It cannot be used with heat-labile materials.
B) It requires an excessively long time to achieve sterilization.
C) It cannot inactivate viruses.
D) It cannot kill endospores.
E) It cannot be used with glassware.

A) It cannot be used with heat-labile materials.

An agent used to reduce the number of bacteria on a toilet would most accurately be called a(n)

A) virucide.
B) antiseptic.
C) disinfectant.
D) aseptic.
E) fungicide.

C) disinfectant.

Application of heat to living cells can result in all of the following EXCEPT

A) breaking of hydrogen bonds.
B) denaturation of enzymes.
C) decreased thermal death time.
D) damage to nucleic acids.
E) alteration of membrane permeability.

C) decreased thermal death time.

Which of the following disinfectants acts by disrupting the plasma membrane?

A) bisphenols
B) soaps
C) halogens
D) aldehydes
E) heavy metals

A) bisphenols

Oxidizing agents include all of the following EXCEPT

A) chlorine.
B) iodine.
C) hydrogen peroxide.
D) glutaraldehyde.
E) ozone.

D) glutaraldehyde

Disinfection of water is achieved by all of the following EXCEPT

A) ozone.
B) peracetic acid.
C) copper sulfate.
D) UV radiation.
E) chlorine.

B) peracetic acid.

All of the following substances are effective against nonenveloped viruses EXCEPT

A) chlorine.
B) ozone.
C) alcohol.
D) ethylene oxide.
E) None of the answers is correct; all of these are equally effective against nonenveloped viruses.

C) alcohol.

Which of the following methods is used to preserve food by slowing the metabolic processes of foodborne microbes?

A) lyophilization
B) nonionizing radiation
C) pasteurization
D) freezing
E) ionizing radiation

D) freezing

Which concentration of ethanol is the most effective bactericide?

A) 100 percent
B) 70 percent
C) 50 percent
D) 40 percent
E) 30 percent

B) 70 percent

All of the following factors contribute to hospital-acquired infections EXCEPT

A) some bacteria metabolize disinfectants.
B) bacteria may be present in commercial products such as mouthwash.
C) gram-negative bacteria are often resistant to disinfectants.
D) invasive procedures can provide a portal of entry for bacteria.
E) None of the answers is correct; all of these factors may contribute to hospital-acquired

E) None of the answers is correct; all of these factors may contribute to hospital-acquired

Which of the following treatments is the most effective for controlling microbial growth?

A) 63°C for 30 minutes
B) 72°C for 15 seconds
C) 140°C for 4 seconds
D) They are equivalent treatments.
E) None of the answers is correct.

D) They are equivalent treatments.

Which of the following could be used to sterilize plastic Petri plates in a plastic wrapper?
A) ultraviolet radiation
B) gamma radiation
C) microwaves
D) sunlight
E) autoclave

B) gamma radiation

Which of the following regarding antimicrobial control agents is FALSE?

A) Contaminating organic debris such as blood or sputum will decrease effectiveness.
B) A true antimicrobial control agent is equally effective against both bacteria and viruses.
C) Some agents affect microbial cell membranes by dissolving lipids.
D) Some agents are utilized as both an antiseptic and a disinfectant.
E) Some agents kill by denaturing microbial cell proteins.

B) A true antimicrobial control agent is equally effective against both bacteria and viruses.

A suspension of 106 Bacillus cereus endospores was put in a hot-air oven at 170°C. Plate counts were used to determine the number of endospores surviving at the time intervals shown.

In Figure 7.1, what is the thermal death time?

A) 150°C
B) 100°C
C) 60 minutes
D) 120 minutes
E) The answer cannot be determined based on the information provided.

C) 60 minutes

In Figure 7.1, the thermal death point for this culture is

A) 15 minutes.
B) 50°C.
C) 170°C.
D) 30 minutes.
E) The answer cannot be determined based on the information provided

E) The answer cannot be determined based on the information provided

In Figure 7.1, the decimal reduction time (D value) for the culture is approximately

A) 0 minutes.
B) 10 minutes. and 15 mins
C) 30 minutes.
D) 40 minutes.
E) 60 minutes.

B) 10 minutes and 15 mins

Which of the following results in lethal damage to nucleic acids?

A) heat
B) radiation
C) certain chemicals
D) heat and radiation
E) heat, radiation, and some chemicals

E) heat, radiation, and some chemicals

Which of the following pairs is mismatched?

A) organic acids — food preservation
B) Ag — wound dressings
C) H2O2 — open wounds
D) CuSO4 — algicide
E) alcohols — open wounds

E) alcohols — open wounds

A disk-diffusion test using Staphylococcus gave the following results:

Disinfectant/ Zone of inhibition (mm)
A / 0
B / 2.5
C / 10
D / 5

In Table 7.1, which compound was the most effective against Staphylococcus?

A) A
B) B
C) C
D) D
E) The answer cannot be determined based on the information provided.

C) C

Disinfectant/ Zone of inhibition (mm)
A / 0
B / 2.5
C / 10
D / 5

In Table 7.1, which compound was the most effective against E. coli? 30)

A) A
B) B
C) C
D) D
E) The answer cannot be determined based on the information provided.

E) The answer cannot be determined based on the information provided.

Disinfectant/ Zone of inhibition (mm)
A / 0
B / 2.5
C / 10
D / 5

In Table 7.1, which compound was bactericidal?

A) A
B) B
C) C
D) D
E) The answer cannot be determined based on the information provided.

E) The answer cannot be determined based on the information provided.

Table 7.2

The fate ofE. coli O157:H7 in apple cider held at 8°C for 2 weeks, with and without preservatives, is shown below:
Bacteria/ml

Cider only > 2.2
Cider with potassium sorbate >2.0
Sodium benzoate > 0
Potassium sorbate + sodium benzoate >0

In Table 7.2, which preservative is most effective?

A) potassium sorbate
B) sodium benzoate
C) potassium sorbate + sodium benzoate
D) no preservative

B) sodium benzoate

An iodophor is a(n)

A) agent that reduces oxygen.
B) form of formaldehyde.
C) quaternary ammonium compound.
D) phenol.
E) iodine mixed with a surfactant.

E) iodine mixed with a surfactant.

Ethylene oxide 3

A) is a good antiseptic.
B) requires high heat to be effective.
C) is not sporicidal.
D) is a sterilizing agent.
E) is the active chemical in household bleach.

D) is a sterilizing agent.

All of the following substances are used to preserve foods EXCEPT

A) nisin.
B) potassium sorbate.
C) calcium propionate.
D) sodium nitrite.
E) biguanides.

E) biguanides.

In Table 7.3, which disinfectant is the most effective at stopping bacterial growth?

A) Doom
B) K.O.
C) Mortum
D) Sterl
E) The answer cannot be determined based on the information provided.

A) Doom

In Table 7.3, which disinfectant was bactericidal?

A) Sterl
B) Doom
C) Mortum
D) K.O.
E) The answer cannot be determined based on the information provided.

C) Mortum

In Table 7.3, which disinfectant was most effective against Salmonella?
A) Sterl
B) Mortum
C) K.O.
D) Doom
E) The answer cannot be determined based on the information provided.

E) The answer cannot be determined based on the information provided.

All of the following are effective for destroying prions EXCEPT

A) NaOH+ autoclaving at 134°C.
B) incineration.
C) proteases.
D) boiling.
E) None of the answers are correct; each of these will destroy prions.

D) boiling.

Which of the following pairs is mismatched?

A) plasma sterilization — free radicals
B) ozone — takes electrons from substances
C) ionizing radiation — hydroxyl radicals
D) supercritical fluids — CO2
E) ultraviolet radiation — desiccation

E) ultraviolet radiation — desiccation

All of the following are methods of food preservation EXCEPT

A) ionizing radiation.
B) microwaves.
C) osmotic pressure.
D) desiccation.
E) high pressure.

B) microwaves.

The preservation of beef jerky from microbial growth relies on which method of microbial control?

A) supercritical CO2
B) filtration
C) ionizing radiation
D) lyophilization
E) desiccation

E) desiccation

If you were preparing nutrient agar at home and did not have an autoclave, what could you use to sterilize the nutrient agar?

A) hydrogen peroxide
B) boiling for one hour
C) oven at 121°C for one hour
D) pressure cooker at 121°C for 15 minutes
E) bleach

D) pressure cooker at 121°C for 15 minutes

Bone and tendons for transplant are decontaminated by

A) plasma sterilization.
B) peroxygens.
C) supercritical fluids.
D) glutaraldehyde.
E) ethylene oxide.

C) supercritical fluids.

Which one of the following is most resistant to chemical biocides?

A) gram-positive bacteria
B) mycobacteria
C) gram-negative bacteria and mycobacteria
D) protozoan cysts
E) viruses with lipid envelopes

C) gram-negative bacteria and mycobacteria

A gene is best defined as

A) a segment of DNA.
B) a sequence of nucleotides in RNA that codes for a functional product.
C) a transcribed unit of DNA.
D) three nucleotides that code for an amino acid.
E) a sequence of nucleotides in DNA that codes for a functional product.

E) a sequence of nucleotides in DNA that codes for a functional product

Which of the following pairs is mismatched?

A) DNA ligase — joins segments of DNA
B) DNA gyrase — coils and twists DNA
C) transposase — insertion of DNA segments into DNA
D) RNA polymerase — makes a molecule of RNA from an RNA template
E) DNA polymerase — makes a molecule of DNA from a DNA template

D) RNA polymerase — makes a molecule of RNA from an RNA template

Which of the following statements is FALSE?

A) DNA polymerase joins nucleotides in one direction only.
B) The leading strand of DNA is made continuously.
C) Multiple replication forks are possible on a bacterial chromosome.
D) DNA replication proceeds in one direction around the bacterial chromosome.
E) The lagging strand of DNA is started by an RNA primer.

D) DNA replication proceeds in one direction around the bacterial chromosome.

DNA is constructed of

A) two strands of nucleotides running antiparallel.
B) a single strand of nucleotides with internal hydrogen bonding.
C) two strands of identical nucleotides with hydrogen bonds between them.
D) two complementary strands of nucleotides bonded A—C and G—T.
E) None of the answers is correct.

A) two strands of nucleotides running antiparallel.

Which of the following is NOT a product of transcription?

A) rRNA
B) tRNA
C) mRNA
D) a new strand of DNA
E) None of the answers are correct; all of these are products of transcription.

D) a new strand of DNA

Which of the following statements about bacteriocins is FALSE?

A) Bacteriocins kill bacteria.
B) They cause food-poisoning symptoms.
C) They can be used to identify certain bacteria.
D) Nisin is a bacteriocin used as a food preservative.
E) The genes coding for them are on plasmids.

B) They cause food-poisoning symptoms.

In Figure 8.1, which colonies are streptomycin-resistant and leucine-requiring?

A) 1, 2, 3, and 9
B) 4, 6, and 8
C) 4 and 8
D) 5 and 6
E) 3 and 9

C) 4 and 8

Table 8.1

Culture 1: F+, leucine+, histidine+

Culture 2: F-, leucine-, histidine-

In Table 8.1, what will be the result of conjugation between cultures 1 and 2?

A) 1 will remain the same;2 will become F+ and recombination may occur
B) 1 will become F-, leu-, his-; 2 will remain the same
C) 1 will become F-, leu+, his+;2 will become F+, leu-, his-
D) 1 will remain the same;2 will become F+, leucine-, histidine-
E) 1 will remain the same;2 will become F+, leu+, his+

D) 1 will remain the same;2 will become F+, leucine-, histidine-

Table 8.1

Culture 1: F+, leucine+, histidine+

Culture 2: F-, leucine-, histidine-

In Table 8.1, if culture 1 mutates to Hfr, what will be the result of conjugation between the two cultures?

A) They will both remain the same.
B) 1 will remain the same; recombination will occur in 2
C) 1 will become F+, leu+, his+; 2 will become F+, leu+, his+
D) 1 will become F-, leu+, his+;2 will become Hfr, leu+, his+
E) The answer cannot be determined based on the information provided.

B) 1 will remain the same; recombination will occur in 2

An enzyme produced in response to the presence of a substrate is called a(n)

A) operator.
B) inducible enzyme.
C) promoter.
D) restriction enzyme.
E) repressible enzyme.

B) inducible enzyme.

When glucose is high, cAMP is _____ : CAP _____ bind the lac operator, and RNA polymerase _____ bind the lac promoter.

A) high; does; does
B) low; does not; does
C) low; does not; does not
D) high; does not; does
E) None of the answers is correct.

C) low; does not; does not

Transformation is the transfer of DNA from a donor to a recipient cell

A) by crossing over.
B) by sexual reproduction.
C) by cell-to-cell contact.
D) as naked DNA in solution.
E) by a bacteriophage.

D) as naked DNA in solution.

Genetic change in bacteria can be brought about by

A) transduction.
B) conjugation.
C) transformation.
D) mutation.
E) All of the answers are correct.

E) All of the answers are correct.

Which of the following statements regarding a bacterium that is R+ is FALSE?

A) R+ can be transferred to a different species.
B) R+ can be transferred to a cell of the same species.
C) It is resistant to certain drugs and heavy metals.
D) It possesses a plasmid.
E) it is F+

E) it is F+

The initial effect of ionizing radiation on a cell is that it causes

A) base substitutions.
B) the formation of highly reactive ions.
C) DNA to break.
D) bonding between adjacent thymines.
E) the cells to get hot.

B) the formation of highly reactive ions.

According to the operon model, for the synthesis of an inducible enzyme to occur, the 1
A) end-product must not be in excess.
B) repressor must bind to the operator.
C) substrate must bind to the repressor.
D) substrate must bind to the enzyme.
E) repressor must not be synthesized.

C) substrate must bind to the repressor.

Synthesis of a repressible enzyme is stopped by the

A) corepressor-repressor complex binding to the operator.
B) corepressor binding to the operator.
C) substrate binding to the repressor.
D) allosteric transition.
E) end product binding to the promoter.

A) corepressor-repressor complex binding to the operator.

In Figure 8.2, if base 4 is thymine, what is base 4′?
A) uracil
B) guanine
C) adenine
D) thymine
E) cytosine

C) adenine

In Figure 8.2, if base 4 is thymine, what is base 11′?
A) adenine
B) cytosine
C) thymine
D) guanine
E) uracil

C) thymine

In Figure 8.2, base 2 is attached to

A) deoxyribose.
B) thymine.
C) phosphate.
D) ribose.
E) The answer cannot be determined based on the information provided.

A) deoxyribose.

The damage caused by ultraviolet radiation is

A) repaired during translation.
B) never repaired.
C) repaired during transcription.
D) repaired by DNA replication.
E) cut out and replaced.

E) cut out and replaced.

Table 8.2
Codon on mRNA and corresponding amino acid

UUA /leucine /UAA /nonsense

GCA /alanine/ AAU /sparagine

AAG /lysine /UGC /cysteine

GUU/ valine/ UCG, UCU/ serine

Refer to Table 8.2. If the sequence of amino acids encoded by a strand of DNA is serine-alanine-lysine-leucine, what is the order of bases in the sense strand of DNA?

A) 3′ TCTCGTTTGTTA
B) 3′ UGUGCAAAGUUA
C) 3′ AGACGTTTCAAT
D) 5′ TGTGCTTTCTTA
E) 5′ AGAGCTTTGAAT

C) 3′ AGACGTTTCAAT

Table 8.2
Codon on mRNA and corresponding amino acid

UUA /leucine /UAA /nonsense

GCA /alanine/ AAU /sparagine

AAG /lysine /UGC /cysteine

GUU/ valine/ UCG, UCU/ serine

Refer to Table 8.2. If the sequence of amino acids encoded by a strand of DNA is serine-alanine-lysine-leucine, the coding for the antisense strand of DNA is

A) 5′ ACAGTTTCAAT.
B) 5′ TCTGCAAAGTTA.
C) 3′ UCUCGAAAGUUA.
D) 3′ UGUGCAAAGUUA.
E) 3′ TCACGUUUCAAU.

B) 5′ TCTGCAAAGTTA.

Table 8.2
Codon on mRNA and corresponding amino acid

UUA /leucine /UAA /nonsense

GCA /alanine/ AAU /sparagine

AAG /lysine /UGC /cysteine

GUU/ valine/ UCG, UCU/ serine

Refer to Table 8.2 The anticodon for valine is
A) CUU.
B) GTA.
C) GUU.
D) CAA.
E) CTT.

D) CAA.

Table 8.2
Codon on mRNA and corresponding amino acid

UUA /leucine /UAA /nonsense

GCA /alanine/ AAU /sparagine

AAG /lysine /UGC /cysteine

GUU/ valine/ UCG, UCU/ serine

Refer to Table 8.2. What is the sequence of amino acids encoded by the following sequence of bases in a strand of DNA?

3′ ATTACGCTTTGC

A) leucine-arginine-lysine-alanine
B) asparagine-cysteine-valine-serine
C) asparagine-arginine-lysine-alanine
D) Translation would stop at the first codon.
E) The answer cannot be determined based on the information provided.

D) Translation would stop at the first codon.

Table 8.2
Codon on mRNA and corresponding amino acid

UUA /leucine /UAA /nonsense

GCA /alanine/ AAU /sparagine

AAG /lysine /UGC /cysteine

GUU/ valine/ UCG, UCU/ serine

Refer to Table 8.2. If a frameshift mutation occurred in the sequence of bases shown below, what would be the sequence of amino acids coded for?

3′ ATTACGCTTTGC

A) asparagine-arginine-lysine-alanine
B) leucine-arginine-lysine-alanine
C) asparagine-cysteine-valine-serine
D) Translation would stop at the first codon.
E) The answer cannot be determined based on the information provided.

E) The answer cannot be determined based on the information provided.

Figure 8.3 – Metabolic Pathway

Gene A / Gene B
Enzyme A / Enzyme B

Compound A->Compound B-> Compound C

In Figure 8.3, if compound C reacts with the allosteric site of enzyme A, this would exemplify

A) a mutation.
B) repression.
C) transcription.
D) competitive inhibition.
E) feedback inhibition.

E) feedback inhibition.

Figure 8.3 – Metabolic Pathway

Gene A / Gene B
Enzyme A / Enzyme B

Compound A->Compound B-> Compound C

In Figure 8.3, if enzyme A is a repressible enzyme, compound C would

A) bind to RNA polymerase.
B) bind to genea.
C) bind to the enzyme.
D) always be in excess.
E) bind to the corepressor.

E) bind to the corepressor.

Figure 8.3 – Metabolic Pathway

Gene A / Gene B
Enzyme A / Enzyme B

Compound A->Compound B-> Compound C

In Figure 8.3, if enzyme A is an inducible enzyme,

A) compound C would react with gene A.
B) compound A would bind to the repressor.
C) compound C would bind to the repressor.
D) compound A would react with enzyme B.
E) compound B would bind to enzyme A.

B) compound A would bind to the repressor.

Conjugation differs from reproduction because conjugation

A) copies RNA to make DNA.
B) replicates DNA.
C) transfers DNA vertically, to new cells.
D) transfers DNA horizontally, to cells in the same generation.
E) transcribes DNA to RNA.

D) transfers DNA horizontally, to cells in the same generation.

The necessary ingredients for DNA synthesis can be mixed together in a test tube. The DNA polymerase is fromThermus aquaticus, and the template is from a human cell. The DNA synthesized would be most similar to

A) human DNA.
B) T. aquaticus DNA.
C) a mixture of human andT. aquaticusDNA.
D) human RNA.
E) T. aquaticus RNA.

A) human DNA.

<b>amino acid encoded chart missing</b>

Based on the information in Table 8.3, prostate cancer is probably the result of which kind of mutation?

A) frameshift
B) missense
C) analog
D) nonsense
E) None of the answers is correct.

D) nonsense

<b>picture missing</b>

In Figure 8.4, the antibiotic chloramphenicol binds the 50S ribosome as shown. From this information you can conclude that chloramphenicol

A) prevents translation in eukaryotes.
B) prevents mRNA-ribosome binding.
C) prevents transcription in prokaryotes.
D) prevents translation in prokaryotes.
E) prevents transcription in eukaryotes.

D) prevents translation in prokaryotes.

The mechanism by which the presence of glucose inhibits the arabinose operon is

A) repression.
B) DNA polymerase.
C) translation.
D) catabolite repression.
E) induction.

D) catabolite repression

The mechanism by which the presence of arabinose controls the arabinose operon is

A) translation.
B) catabolite repression.
C) induction.
D) DNA polymerase.
E) repression.

C) induction.

If you knew the sequence of nucleotides within a gene, which one of the following could you determine with the most accuracy?

A) the primary structure of the protein
B) the secondary structure of the protein
C) the tertiary structure of the protein
D) the quaternary structure of the protein
E) The answer cannot be determined based on the information provided.

A) the primary structure of the protein

An enzyme that makes covalent bonds between nucleotide sequences in DNA is

A) transposase.
B) DNA ligase
C) RNA polymerase.
D) DNA polymerase.
E) DNA helicase.

B) DNA ligase

An enzyme that copies DNA to make a molecule of RNA is

A) DNA ligase.
B) DNA helicase.
C) transposase.
D) RNA polymerase.
E) DNA polymerase.

D) RNA polymerase.

An enzyme that catalyzes the cutting and resealing of DNA, and is translated from insertion sequences, is

A) transposase.
B) DNA ligase.
C) DNA helicase.
D) DNA polymerase.
E) RNA polymerase.

A) transposase.

Repair of damaged DNA might be viewed as a race between an endonuclease and

A) primase.
B) DNA ligase.
C) helicase.
D) DNA polymerase.
E) methylase.

E) methylase.

The cancer generas produces mRNA containing an extra exon that includes a number of UAA codons. Cancer cells produce ras mRNA missing this exon. This mistake most likely is due to a mistake by

A) UV radiation.
B) a chemical mutagen.
C) snRNPs.
D) photolyases.
E) DNA polymerase.

C) snRNPs.

The miRNAs in a cell

A) are found in prokaryotic cells.
B) are a part of the eukaryotic ribosome.
C) are responsible for inducing operons.
D) are a part of the prokaryotic ribosome.
E) allow different cells to produce different proteins.

E) allow different cells to produce different proteins.

Assume the twoE.coli strains shown below are allowed to conjugate.

Hfr: pro+, arg+, his+, lys+, met+, ampicillin-sensitive

F: pro-, arg-, his-, lys-, met-, ampicillin-resistant

What supplements would you add to glucose minimal salts agar to select for a recombinant cell that is lys+, arg+, amp-resistant?

A) ampicillin, lysine, arginine
B) ampicillin, proline, histidine, methionine
C) lysine, arginine
D) proline, histidine, methionine
E) ampicillin, prolein, histidine, lysine

B) ampicillin, proline, histidine, methionine

Protein synthesis in eukaryotes is similar to the process in prokaryotes in that both eukaryotes and prokaryotes

A) have exons.
B) use codons to determine polypeptide sequences. and arrange amino acids
C) have introns.
D) use methionine as the "start" amino acid.
E) require snRNPS.

B) use codons to determine polypeptide sequences. and arrange amino acids

Place the following surfactants in order from the most effective to the least effective antimicrobial activity: 1-Soap; 2-Acid-anionic detergent; 3-Quats.

A) 1, 2, 3
B) 1, 3, 2
C) 2, 1, 3
D) 3, 2, 1
E) 3, 1, 2

D) 3, 2, 1

Iodophors differ from iodine (I2) in that iodophors

A) Don’t stain.
B) Are less irritating.
C) Are longer lasting.
D) Are combined with a nonionic detergent.
E) All of the above.

E) All of the above.

Which of the following affects the elimination of bacteria from an object?

A) Number of bacteria present
B) Temperature
C) pH
D) Presence of organic matter
E) All of the above

E) All of the above

Which of the following does NOT directly result from application of heat?

A) Breaking of hydrogen bonds
B) Breaking of sulfhydryl bonds
C) Denaturing of enzymes
D) Cell lysis
E) Damage to nucleic acids

D) Cell lysis

Which of these disinfectants acts by denaturing proteins?

A) Alcohols
B) Aldehydes
C) Bisphenols
D) Halogens
E) Phenolics

C) Bisphenols

Which of the following substances is NOT an oxidizing agent?

A) Chlorine
B) Glutaraldehyde
C) Hydrogen peroxide
D) Iodine
E) Ozone

B) Glutaraldehyde

Which of the following is NOT used to disinfect water?

A) Ozone
B) Gamma radiation
C) Chlorine
D) Copper sulfate
E) Heat

E) Heat

Which of the following substances is NOT effective against nonenveloped viruses?

A) Alcohol
B) Chlorine
C) Ethylene oxide
D) Ozone
E) All are equally effective.

A) Alcohol

Glutaraldehyde is considered one of the most effective disinfectants for hospital use. Which of the following statements about glutaraldehyde is false?

A) Stains and corrodes
B) Is safe to transport
C) Acts rapidly
D) Is not hampered by organic material
E) Attacks all microorganisms

A) Stains and corrodes

Which of the following is NOT a factor contributing to hospital-acquired infections?

A) Some bacteria metabolize disinfectants.
B) Gram-negative bacteria are often resistant to disinfectants.
C) Invasive procedures can provide a portal of entry for bacteria.
D) Bacteria may be present in commercial products such as mouthwash.
E) All of the above may contribute to hospital-acquired infection.

E) All of the above may contribute to hospital-acquired infection.

Assume that one culture is a freshly opened package of dried yeast with 0.1% moisture, another culture is the same yeast with 7.5% moisture, and the third culture is a package of yeast mixed with water. Each culture was exposed to 130°C in a hot-air oven. Which graph in Figure 7.1 most likely shows the yeast with 0.1% moisture?
A) a
B) b
C) c
D) a and b
E) b and c

C) c

Which one of the following does NOT belong with the others?

A) Acid-anionic detergents
B) Benzoic acid
C) Supercritical CO2
D) Pasteurization
E) Peracetic acid

A) Acid-anionic detergents

Which one of the following does NOT belong with the others?

A) Beta-propiolactone
B) Glutaraldehyde
C) Ethylene oxide
D) Hydrogen peroxide
E) Propylene oxide

D) Hydrogen peroxide

Which of the following will NOT inactivate endospores?

A) Autoclave
B) Chlorine dioxide
C) High pressure
D) Plasma
E) Supercritical CO2

C) High pressure

The reaction catalyzed by reverse transcriptase is

A) mRNA protein.
B) mRNA cDNA.
C) DNA DNA.
D) DNA mRNA.
E) tRNA mRNA.

B) mRNA cDNA.

Biotechnology involves the

A) use of microorganisms to make desired products.
B) use of animal cells to make vaccines.
C) development of disease-resistant crop plants.
D) use of microorganisms to make desired products and the use of animal cells to make vaccines.
E) use of microorganisms to make desired products, the use of animal cells to make vaccines, and the development of disease-resistanct crop plants.

E) use of microorganisms to make desired products, the use of animal cells to make vaccines, and the development of disease-resistanct crop plants.

Which of the following is NOT a desired characteristic of DNA vectors used in gene cloning procedures?

A) large size
B) may replicate in several species
C) circular form of DNA or integrates into the host chromosome
D) has a selectable marker
E) self-replication

A) large size

*<b>picture missing</b>*

In Figure 9.4, the bacteria transformed with the recombinant plasmid and plated on media containing ampicillin and X-gal will

A) form white, ampicillin-sensitive colonies.
B) form blue, ampicillin-sensitive colonies.
C) form white, ampicillin-resistant colonies.
D) form blue, ampicillin-resistant colonies.
E) not grow.

C) form white, ampicillin-resistant colonies.

An advantage of synthetic DNA over genomic or cDNA is the ability to

A) insert desired restriction sites into the DNA sequence.
B) obtain genes that lack introns.
C) obtain genes that lack exons.
D) make DNA from cellular RNA and the enzyme reverse transcriptase.
E) isolate unknown genes.

A) insert desired restriction sites into the DNA sequence.

An advantage of cDNA over genomic DNA is that it 1

A) lacks introns.
B) lacks exons.
C) contains selectable markers.
D) is very easy to isolate.
E) can form very large DNA segments.

A) lacks introns.

The restriction enzymeEcoRI recognizes the sequence GAATTC. Which of the following is TRUE of DNA after it is treated with EcoRI?

A) All of the DNA will be circular.
B) All of the DNA fragments will have single-stranded regions ending in AA.
C) All of the DNA will have blunt ends.
D) All of the DNA fragments will have single-stranded regions ending in G.
E) Some of the DNA will have single-stranded regions ending in AA and others will end in G.

B) All of the DNA fragments will have single-stranded regions ending in AA.

The Human Genome Project, which was completed in 2003, was focused on

A) identifying all of the genes in the human genome.
B) finding a cure for all human genetic disorders.
C) determining all of the proteins encoded by the human genome.
D) determining the nucleotide sequence of the entire human genome.
E) cloning all of the genes of the human genome.

D) determining the nucleotide sequence of the entire human genome.

Which of the following places the steps in the PCR procedure in the correct order?

1) Incubate at 94°C to denature DNA strands; 2) Incubate at 72°C for DNA synthesis;

3) Incubate at 60°C for primer hybridization.

A) 2; 1; 3
B) 1, 3, 2
C) 3, 2, 1
D) 3; 1; 2
E) 1, 2, 3

B) 1, 3, 2

Which of the following are used to silence specific genes and hold promise for treating cancer or viral diseases, such as hepatitis B?

A) DNA fingerprinting
B) RNA interference (RNAi)
C) reverse transcriptase PCR (rtPCR)
D) complementary DNA (cDNA)
E) tumor-inducing plasmids (Ti plasmids)

B) RNA interference (RNAi)

Which of the following techniques is NOT used to introduce recombinant DNA into plants?

A) microinjection
B) Ti plasmids andAgrobacterium
C) gene guns
D) protoplast fusion
E) electroporation

A) microinjection

In Figure 9.5, the marker genes used for selecting recombinant DNA are

A) lacZ and ori.
B) HindIII,BamHI, andEcoRI.
C) ampR and lacZ.
D) ori.
E) ampR and ori.

C) ampR and lacZ.

In Figure 9.5, the gene that allows the plasmid to be self-replicating is

A) HindIII.
B) EcoRI.
C) ampR.
D) lacZ.
E) ori.

E) ori.

Which of the following methods would be used to introduce the plasmid shown in Figure 9.5 into E. coli?

A) transformation
B) gene guns
C) Ti plasmids andAgrobacterium
D) microinjection

A) transformation

Which of the following are used by the Centers for Disease Control and Prevention to track outbreaks of foodborne disease?

A) DNA fingerprints
B) restriction fragment length polymorphisms
C) reverse-transcriptase PCR (rtPCR)
D) DNA fingerprings and restriction fragment length polymorphisms
E) DNA fingerprings, restriction fragment length polymorphisms, and reverse-transcriptase PCR(rtPCR)

E) DNA fingerprings, restriction fragment length polymorphisms, and reverse-transcriptase PCR(rtPCR)

The use of "suicide" genes in genetically modified organisms is designed to

A) delete genes necessary for modified organism’s growth.
B) prevent the growth of the modified organisms in the environment.
C) provide a means to eliminate non-modified organisms.
D) provide for resistance of the modified organisms to pesticides.
E) kill the modified organisms before they are released in the environment.

B) prevent the growth of the modified organisms in the environment.

In the Southern blot technique, which of the following is NOT required?

A) transfer of DNA to nitrocellulose
B) restriction enzyme digestion of DNA
C) addition of a labeled probe to identify the gene of interest
D) addition of heat-stable DNA polymerase to amplify DNA
E) electrophoresis to separate fragments

D) addition of heat-stable DNA polymerase to amplify DNA

The random shotgun method is used in

A) forensic microbiology.
B) transforming plant cells with recombinant DNA.
C) RFLP analysis.
D) amplification of unknown DNA.
E) genome sequencing.

E) genome sequencing.

The study of genetic material taken directly from the environment is

A) proteomics.
B) reverse genetics.
C) forensic microbiology.
D) metagenomics.
E) bioinformatics.

D) metagenomics.

The reaction catalyzed by DNA polymerase is

A) DNA → mRNA
B) mRNA → cDNA
C) mRNA → protein
D) DNA → DNA
E) tRNA → mRNA

D) DNA → DNA

Which of the following methods of making rDNA could be described as "hit or miss"?

A) Protoplast fusion
B) Viral transduction
C) Transformation
D) Cloning
E) Gene gun

A) Protoplast fusion

Suicide genes can be controlled by the fimbriae-gene operator. This would result in the death of

A) All cells.
B) Cells making flagella.
C) Cells making fimbriae.
D) Cells at 37°C.
E) Conjugating cells.

C) Cells making fimbriae.

E. coli makes insulin because

A) It needs to regulate its cell-glucose level.
B) It’s an ancient gene that now has no function.
C) The insulin gene was inserted into it.
D) It picked up the insulin gene from another cell.
E) No reason; it doesn’t make insulin.

C) The insulin gene was inserted into it.

Subunit vaccines can be made by genetic modification of yeast cells. A side effect of these vaccines might be

A) The disease.
B) A yeast infection.
C) Due to extraneous material.
D) Failure of the vaccine to provide immunity.
E) None of the above.

E) None of the above.

The value of cDNA in recombinant DNA is that

A) It lacks exons.
B) It lacks introns.
C) It’s really RNA.
D) It contains introns and exons.

B) It lacks introns.

Which enzyme does NOT make sticky ends?

A) Enzyme Recognition
BamHI G↓GATCC
CCTAG↑G
B) Enzyme Recognition
EcoRI G↓AATTC
CTTAA↑G
C) Enzyme Recognition
HaeIII GG↓CC
CC↑GG
D) Enzyme Recognition
HindIII A↓AGCTT
TTCGA↑A
E) Enzyme Recognition
PstI CTGC↓G G↑ACGTC

C) Enzyme Recognition HaeIII GG↓CC CC↑GG

The purpose of the Human Genome Project was to

A) Identify all of the human genes.
B) Sequence the nucleotides in human DNA.
C) Translate human DNA.
D) Identify genes of all organisms.
E) None of the above.

B) Sequence the nucleotides in human DNA.

You have a small gene that you wish replicated by PCR. You add radioactively labeled nucleotides to the PCR thermocycler. After 3 replication cycles, what percentage of the DNA single strands are radioactively labeled?

A) 0%
B) 12.5%
C) 50%
D) 87.5%
E) 100%

D) 87.5%

(chptr 9 10th ed. picture)
In Figure 9.4, the resulting organism (a) is

A) Bacillus thuringiensis.
B) Pseudomonas fluorescens.
C) A tomato plant.
D) E. coli.
E) a plant × Pseudomonas hybrid.

C) A tomato plant.

(chptr 9 10th ed. picture)
In Figure 9.4, the resulting P. fluorescens has

A) A tomato gene.
B) An E. coli gene.
C) A Bacillus gene.
D) A tomato and a Bacillus gene.
E) No new gene.

C) A Bacillus gene.

(chptr 9 10th ed. picture)
In Figure 9.4, the purpose of this experiment is to

A) Put a gene into a plant.
B) Put an insecticide on plant leaves.
C) Put a gene in Bacillus.
D) Isolate Pseudomonas from a plant.
E) Make a better tomato.

B) Put an insecticide on plant leaves.

(chptr 9 10th ed. picture)
In Figure 9.4, the vector is

A) A virus.
B) A plasmid.
C) A library.
D) RNA.
E) Pseudomonas.

…

(chptr 9 10th ed. picture)
In Figure 9.4, the process required in step 5 is

A) Transformation.
B) Southern blotting.
C) PCR.
D) Transcription.
E) Conjugation.

A) Transformation.

To see the results of your work in question 33, you need to use

A) Northern blotting.
B) Southern blotting.
C) Western blotting.
D) Colony blotting.
E) Selection.

B) Southern blotting.

Large numbers of bacterial cells are NOT found in crown galls because

A) The plant kills the bacteria.
B) Cell walls protect the plant from bacterial invasion.
C) A gene in plant cells is controlling growth.
D) Bacteria kill plants.
E) The assumption is not true; many bacteria are in the galls.

C) A gene in plant cells is controlling growth.

A specific gene can be inserted into a cell by all of the following EXCEPT

A) Protoplast fusion.
B) A gene gun.
C) Microinjection.
D) Electroporation.
E) Agrobacterium.

A) Protoplast fusion.

PCR can be used to amplify DNA in a clinical sample. The following steps are used in PCR. What is the fourth step?

A) Collect DNA.
B) Incubate at 94°C.
C) Incubate at 60°C.
D) Incubate at 72°C.
E) Add DNA polymerase.

C) Incubate at 60°C.

Which of the following processes CANNOT be used to insert foreign DNA into cells?

A) Transformation
B) Electroporation
C) Protoplast fusion
D) A gene gun
E) All of the above can be used to insert foreign DNA into cells.

E) All of the above can be used to insert foreign DNA into cells.

An enzyme that cuts double-stranded DNA at specific nucleotide sequences.

A) RNA polymerase
B) DNA ligase
C) Restriction enzyme
D) Transposase
E) DNA polymerase

C) Restriction enzyme

In transcription,

A) DNA is changed to RNA.
B) DNA is copied to RNA.
C) DNA is replicated.
D) RNA is copied to DNA.
E) Proteins are made.

B) DNA is copied to RNA.