micro exam 2 ch. 7-11 Flashcards

Which of the following regarding antimicrobial control agents is FALSE?
Select one:
a. Some agents are utilized as both an antiseptic and a disinfectant.
b. A true antimicrobial control agent is equally effective against both bacteria and viruses.
c. Some agents kill by denaturing microbial cell proteins.
d. Some agents affect microbial cell membranes by dissolving lipids.
e. Contaminating organic debris such as blood or sputum will decrease effectiveness.

Which of the following results in lethal damage to nucleic acids?
Select one:
a. heat
b. radiation
c. certain chemicals
d. heat and radiation
e. heat, radiation, and some chemicals

An agent used to reduce the number of bacteria on a toilet would most accurately be called aNo
Select one:
a. disinfectant.
b. aseptic.
c. fungicide.
d. antiseptic.
e. virucide.

Which of the following is the best method to sterilize heat-labile solutions?
Select one:
a. dry heat
b. membrane filtration
c. pasteurization
d. autoclave
e. freezing

Which of the following chemical agents is used for sterilization?
Select one:
a. phenolics
b. chlorine
c. ethylene oxide

d. soap
e. alcohol

Any process that destroys the non-spore forming contaminants on inanimate objects is sterilization.
Select one:
True
False

Which of the following treatments is the most effective for controlling microbial growth?
Select one:
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.

Which of the following pairs of terms is mismatched?
Select one:
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

Which of the following disinfectants acts by disrupting the plasma membrane?
Select one:
a. aldehydes
b. heavy metals
c. soaps
d. halogens
e. bisphenols

If you were preparing nutrient agar at home and did not have an autoclave, what could you use to sterilize the nutrient agar?
Select one:
a. oven at 121°C for one hour
b. boiling for one hour
c. bleach
d. hydrogen peroxide
e. pressure cooker at 121°C for 15 minutes

Disinfection of water is achieved by all of the following EXCEPT
Select one:
a. chlorine.
b. peracetic acid.
c. ozone.
d. UV radiation.
e. copper sulfate.

The thermal death time is the time needed to kill all the bacteria in a particular culture at a certain temperature.
Select one:
True
False

The preservation of beef jerky from microbial growth relies on which method of microbial control?
Select one:
a. filtration
b. desiccation
c. supercritical CO2
d. ionizing radiation
e. lyophilization

Which of the following regarding antimicrobial control agents is FALSE?
Select one:
a. Contaminating organic debris such as blood or sputum decrease effectiveness.
b. Silver is used for treating antibiotic-resistant bacteria.
c. Some agents inactivate viruses by attacking cell membrane lipids.
d. Some agents kill by denaturing microbial cell proteins.
e. Some agents affect microbial cell membranes by dissolving lipids.

Which of the following pairs is mismatched?
Select one:
a. CuSO4 - algicide
b. organic acids - food preservation
c. alcohols - open wounds
d. H2O2 - open wounds
e. Ag - wound dressings

Which of the following could be used to sterilize plastic Petri plates in a plastic wrapper?
Select one:
a. microwaves
b. autoclave
c. ultraviolet radiation
d. sunlight
e. gamma radiation

Application of heat to living cells can result in all of the following EXCEPT
Select one:
a. denaturation of enzymes.
b. alteration of membrane permeability.
c. damage to nucleic acids.
d. breaking of hydrogen bonds.
e. decreased thermal death time.

Moist heat destroys organisms by denaturing proteins.
Select one:
True
False

Pseudomonas has been found growing in quaternary ammonium compounds (quats).
Select one:
True
False

Which of the following is a limitation of the autoclave?
Select one:
a. It requires an excessively long time to achieve sterilization.
b. It cannot inactivate viruses.
c. It cannot be used with glassware.
d. It cannot kill endospores.
e. It cannot be used with heat-labile materials.

PCR can be used to identify an unknown bacterium because
Select one:
a. the RNA primer is specific.
b. DNA polymerase will replicate DNA.
c. DNA can be electrophoresed.
d. all cells have DNA.
e. all cells have RNA.

Which of the following is NOT a product of transcription?
Select one:
a. tRNA
b. a new strand of DNA
c. mRNA
d. rRNA
e. None of the answers are correct; all of these are products of transcription.

An enzyme that makes covalent bonds between nucleotide sequences in DNA is
Select one:
a. DNA ligase
b. DNA polymerase.
c. DNA helicase.
d. transposase.
e. RNA polymerase.

Synthesis of a repressible enzyme is stopped by the
Select one:
a. substrate binding to the repressor.
b. corepressor-repressor complex binding to the operator.
c. corepressor binding to the operator.
d. allosteric transition.
e. end product binding to the promoter.

Cell-to-cell contact is required for transduction to occur.
Select one:
True
False

In the Ames test, any colonies that form on the control should be the result of spontaneous mutations.
Select one:
True
False

An enzyme that copies DNA to make a molecule of RNA is
Select one:
a. transposase.
b. DNA ligase.
c. RNA polymerase.
d. DNA polymerase.
e. DNA helicase.

Which of the following is an advantage of using E. coli to make a human gene product?
Select one:
a. It cannot process introns.
b. It does not secrete most proteins.
c. Its genes are well known.
d. Endotoxin may be in the product.
e. Endotoxin may be in the product and it does not secrete most proteins.

n the Southern blot technique, which of the following is NOT required?
Select one:
a. restriction enzyme digestion of DNA
b. transfer of DNA to nitrocellulose
c. electrophoresis to separate fragments
d. addition of heat-stable DNA polymerase to amplify DNA
e. addition of a labeled probe to identify the gene of interest

Protein synthesis in eukaryotes is similar to the process in prokaryotes in that both eukaryotes and prokaryotes
Select one:
a. use codons to determine polypeptide sequences.
b. have exons.
c. have introns.
d. use methionine as the "start" amino acid.
e. require snRNPS.

The disadvantage of genomic libraries over cDNA libraries is that genomic libraries contain gene introns.
Select one:
True
False

Assume the two E.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?
Select one:
a. lysine, arginine
b. ampicillin, prolein, histidine, lysine
c. ampicillin, proline, histidine, methionine
d. proline, histidine, methionine
e. ampicillin, lysine, arginine

A gene is best defined as
Select one:
a. three nucleotides that code for an amino acid.
b. a transcribed unit of DNA.
c. a sequence of nucleotides in DNA that codes for a functional product.
d. a segment of DNA.
e. a sequence of nucleotides in RNA that codes for a functional product.

In recombinant DNA technology, a vector is a self-replicating segment of DNA, such as a plasmid or viral genome.
Select one:
True
False

The random shotgun method is used in
Select one:
a. forensic microbiology.
b. transforming plant cells with recombinant DNA.
c. RFLP analysis.
d. genome sequencing.
e. amplification of unknown DNA.

An enzyme produced in response to the presence of a substrate is called aNo
Select one:
a. repressible enzyme.
b. restriction enzyme.
c. promoter.
d. operator.
e. inducible enzyme.

Recombination will always alter a cell's genotype.
Select one:
True
False

The initial effect of ionizing radiation on a cell is that it causes
Select one:
a. base substitutions.
b. the cells to get hot.
c. the formation of highly reactive ions.
d. bonding between adjacent thymines.
e. DNA to break.

The miRNAs in a cell inhibit protein synthesis by forming complementary bonds with rRNA.
Select one:
True
False

The restriction enzyme EcoRI recognizes the sequence G↓AATTC. Which of the following is TRUE of DNA after it is treated with EcoRI?
Select one:
a. All of the DNA fragments will have single-stranded regions ending in AA.
b. All of the DNA fragments will have single-stranded regions ending in G.
c. Some of the DNA will have single-stranded regions ending in AA and others will end in G.
d. All of the DNA will be circular.
e. All of the DNA will have blunt ends.

Transposition results in the formation of base substitution mutations in a cell's DNA.
Select one:
True
False

Which of the following is NOT an agricultural product made by DNA techniques?
Select one:
a. Bacillus thuringiensis insecticide
b. nitrogenase (nitrogen fixation)
c. glyphosate-resistant crops
d. frost retardant
e. pectinase

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.
Select one:
a. 3; 1; 2
b. 3, 2, 1
c. 1, 2, 3
d. 2; 1; 3
e. 1, 3, 2

The following steps must be performed to make a bacterium produce human protein X.

1-Translation
2-Restriction enzyme
3-Prokaryotic transcription
4-DNA ligase
5-Transformation
6-Eukaryotic transcription
7-Reverse transcription

Which of the following places the steps in the correct order?
Select one:
a. 1, 2, 3, 5, 4, 7, 6
b. 6, 7, 2, 3, 4, 5, 1
c. 5, 2, 3, 4, 7, 6, 1
d. 6, 7, 2, 4, 5, 3, 1
e. 6, 2, 1, 3, 4, 5, 7

Which of the following statements about bacteriocins is FALSE?
Select one:
a. Bacteriocins kill bacteria.
b. The genes coding for them are on plasmids.
c. They cause food-poisoning symptoms.
d. Nisin is a bacteriocin used as a food preservative.
e. They can be used to identify certain bacteria.

The Human Genome Project, which was completed in 2003, was focused on
Select one:
a. finding a cure for all human genetic disorders.
b. determining the nucleotide sequence of the entire human genome.
c. identifying all of the genes in the human genome.
d. determining all of the proteins encoded by the human genome.
e. cloning all of the genes of the human genome.

The following are steps used to make DNA fingerprints. What is the third step?
Select one:
a. Lyse cells.
b. Add stain.
c. Digest with a restriction enzyme.
d. Perform electrophoresis.
e. Collect DNA.

Some organisms may contain multiple genomes.
Select one:
True
False

Which of the following are used to silence specific genes and hold promise for treating cancer or viral diseases, such as hepatitis B?
Select one:
a. complementary DNA (cDNA)
b. DNA fingerprinting
c. RNA interference (RNAi)
d. tumor-inducing plasmids (Ti plasmids)
e. reverse transcriptase PCR (rtPCR)

The Pap test for cervical cancer involves microscopic examination of cervical cells for cancerous cells. A new, rapid diagnostic test to detect human papilloma virus (HPV) DNA before cancer develops is done without microscopic exam. The steps involved in this FastHPV test are listed below. What is the second step?
Select one:
a. Lyse human cells.
b. Add enzyme-linked antibodies against DNA-RNA.
c. Add enzyme substrate.
d. Add an RNA probe for HPV DNA.
e. The order is unimportant.

The reaction catalyzed by reverse transcriptase is
Select one:
a. DNA → DNA.
b. DNA → mRNA.
c. mRNA → cDNA.
d. mRNA → protein.
e. tRNA → mRNA.

Pieces of DNA stored in yeast cells are called a
Select one:
a. clone.
b. Southern blot.
c. PCR.
d. vector.
e. library.

Both base substitution and frameshift mutations can result in the formation of premature stop codons.
Select one:
True
False

A source of heat-stable DNA polymerase is
Select one:
a. Bacillus thuringiensis.
b. Agrobacterium tumefaciens.
c. Pseudomonas.
d. Thermus aquaticus.
e. Saccharomyces cerevisiae.

Transformation is the transfer of DNA from a donor to a recipient cell
Select one:
a. by sexual reproduction.
b. by a bacteriophage.
c. by cell-to-cell contact.
d. as naked DNA in solution.
e. by crossing over.

If you have inserted a gene in the Ti plasmid, the next step in genetic engineering is
Select one:
a. inserting the Ti plasmid into a plant cell.
b. splicing T DNA into a plasmid.
c. transformation of E. coli with Ti plasmid.
d. transformation of an animal cell.
e. inserting the Ti plasmid into Agrobacterium.

Genetic change in bacteria can be brought about by
Select one:
a. conjugation.
b. transformation.
c. transduction.
d. mutation.
e. All of the answers are correct.

DNA is constructed of
Select one:
a. a single strand of nucleotides with internal hydrogen bonding.
b. two complementary strands of nucleotides bonded A-C and G-T.
c. two strands of identical nucleotides with hydrogen bonds between them.
d. two strands of nucleotides running antiparallel.
e. None of the answers is correct.

Restriction enzymes are
Select one:
a. bacterial enzymes that destroy phage DNA.
b. bacterial enzymes that splice DNA.
c. viral enzymes that destroy host DNA.
d. animal enzymes that splice RNA.

The use of an antibiotic-resistance gene on a plasmid used in genetic engineering makes
Select one:
a. direct selection possible.
b. the recombinant cell unable to survive.
c. replica plating possible.
d. the recombinant cell dangerous.
e. All of the answers are correct.

At this point in time, scientists believe the vast majority of the domain Bacteria have been discovered.
Select one:
True
False

The highest level in the taxonomic hierarchy is "Kingdom."
Select one:
True
False

Which of the following criteria is most useful in determining whether two organisms are related?
Select one:
a. Both are aerobic.
b. Both are motile.
c. Both are gram-positive.
d. Both ferment lactose.
e. Each answer is equally important.

The cell membranes of all three domains are composed of straight carbon chains attached to
glycerol by ester linkage.
Select one:
True
False

One of the most popular taxonomic tools is DNA fingerprinting to develop profiles of organisms. These profiles provide direct information about
Select one:
a. the similarities between nucleotide sequences.
b. the presence of specific genes.
c. antigenic composition.
d. protein composition.
e. enzymatic activities.

Into which group would you place a multicellular heterotroph with chitin cell walls?
Select one:
a. Plantae
b. Archaea
c. Fungi
d. Animalia
e. Bacteria

Once a culture is purified, the next step in the process of identifying bacteria is biochemical testing.
Select one:
True
False

Which of the following best defines a strain?
Select one:
a. a group of organisms with a limited geographical distribution
b. a population of cells with similar characteristics
c. same as a species
d. a pure culture that is not totally identical to other cultures of the same species
e. a group of cells derived from a single parent

Protists are a diverse group of organisms that are similar in
Select one:
a. metabolic type.
b. rRNA sequences.
c. motility.
d. ecology.
e. None of the answers is correct.

Into which group would you place a unicellular organism that has 70S ribosomes and a peptidoglycan cell wall?
Select one:
a. Protist
b. Animalia
c. Fungi
d. Plantae
e. Bacteria

Nucleic acid hybridization is based on the fact that
Select one:
a. all cells have DNA.
b. the strands of DNA can be separated.
c. pairing between complementary bases occurs.
d. DNA is composed of genes.
e. a chromosome is composed of complementary strands.

Biochemical tests are used to determine
Select one:
a. amino acid sequences.
b. nucleic acid-base composition.
c. enzymatic activities.
d. staining characteristics.
e. All of the answers are correct.

Into which group would you place a multicellular organism that has a mouth and lives inside the human liver?
Select one:
a. Animalia
b. Fungi
c. Plantae
d. Proteobacteria (gram-negative bacteria)
e. Firmicutes (gram-positive bacteria)

Which of the following statements is a reason for NOT classifying viruses in one of three
domains rather than in a fourth domain?
Select one:
a. Some viruses can incorporate their genome into a host's genome.
b. Viruses direct anabolic pathways of host cells.
c. Viruses are not composed of cells.
d. Viruses are obligate parasites.
e. All of the answers are correct.

A genus can best be defined as
Select one:
a. a taxon composed of one or more species and below family.
b. the most specific taxon.
c. a taxon comprised of classes.
d. a taxon composed of families.
e. a taxon belonging to a species.

A bacterial species differs from a species of eukaryotic organisms in that a bacterial species
Select one:
a. breeds with its own species.
b. does not breed with other species.
c. has a limited geographical distribution.
d. is a population of cells with similar characteristics.
e. can be distinguished from other bacterial species.

Which of the following characterizes the Domain Bacteria?
Select one:
a. prokaryotic cells; ether linkages in phospholipids
b. prokaryotic cells; ester linkages in phospholipids
c. eukaryotic cells; ester linkages in phospholipids
d. multicellular
e. complex cellular structures

A clone is
Select one:
a. a taxon composed of species.
b. a genetically engineered cell.
c. a mound of cells on an agar medium.
d. genetically identical cells derived from a single cell.
e. None of the answers is correct

Pure cultures of the same species are not always identical in all ways.
Select one:
True
False

You discovered a unicellular organism that lacks a nucleus and peptidoglycan. You suspect the organism is in the group
Select one:
a. Animalia.
b. Bacteria.
c. Archaea.
d. Plantae.
e. Fungi.

Which of the following pairs is NOT correctly matched?
Select one:
a. heterocyst cyanobacteria
b. endospore Bacillus
c. elementary body Escherichia
d. endospore Clostridium
e. myxospore gliding bacteria

Photosynthetic organisms always produce oxygen gas as a metabolic byproduct.
Select one:
True
False

Which of the following is NOT a characteristic inherent of the non-endospore-forming gram-positive rods?
Select one:
a. lack cell walls
b. are aerotolerant
c. carry out fermentative metabolism
d. nonpathogenic
e. display a branched filamentous morphology

Which of the following is NOT a characteristic of Neisseria?
Select one:
a. oxidase-positive
b. cocci
c. requires X and V factors
d. gram-negative
e. Some species are human pathogens.

Mycoplasmas differ from other bacteria in that they
Select one:
a. are acid-fast.
b. are gram-negative.
c. grow inside host cells.
d. lack a cell wall.
e. are motile.

Requirements for X and V factors are used to identify
Select one:
a. Neisseria.
b. Pseudomonas.
c. Haemophilus.
d. Escherichia.
e. Staphylococcus.

The Gram stain is not suitable for identifying members of the Archaea.
Select one:
True
False

Which of the following is the best reason to classify Streptococcus in the Lactobacillales?
Select one:
a. found in dairy products
b. Gram reaction
c. fermentation of lactose
d. rRNA sequences
e. morphology

Which of the following lacks a cell wall?
Select one:
a. Mycoplasma
b. Borrelia
c. Mycobacterium
d. Nocardia
e. Clostridium

Which one of the following does NOT belong with the others?
Select one:
a. Wolbachia IncorrectIncorrect
b. Ehrlichia
c. Coxiella
d. Rickettsia
e. Staphylococcus

Which of the following bacteria are responsible for more infections and more different kinds of infections?
Select one:
a. Neisseria
b. Staphylococcus
c. Pseudomonas
d. Streptococcus
e. Salmonella

Which of the following is NOT an enteric?
Select one:
a. Salmonella
b. Shigella
c. Campylobacter
d. Enterobacter
e. Escherichia

You have isolated a gram-positive rod. What should you do next?
Select one:
a. enterotube
b. lactose fermentation
c. flagella stain
d. endospore stain
e. Gram stain

You have isolated an aerobic gram-positive, endospore-forming bacterium that grows well on nutrient agar. To which of the following groups does it most likely belong?
Select one:
a. gammaproteobacteria
b. deltaproteobacteria
c. phototrophic bacteria
d. bacillales
e. The answer cannot be determined based on the information provided.

Which of the following form conidiospores?
Select one:
a. rickettsias
b. endospore-forming gram-positive rods and cocci
c. spiral and curved bacteria
d. actinomycetes and related organisms
e. anaerobic gram-negative cocci

Burkholderia was reclassified from the gammaproteobacteria to the betaproteobacteria because
Select one:
a. it is a gram-negative rod.
b. it causes melioidosis.
c. it causes infections in cystic fibrosis patients.
d. its rRNA sequence is similar to that of Neisseria.
e. it grows in disinfectants.

Which one of the following bacteria does NOT belong with the others?
Select one:
a. Campylobacter
b. Burkholderia
c. Salmonella
d. Pseudomonas
e. Bordetella

Which of the following bacteria does NOT belong with the others?
Select one:
a. Halobacterium
b. Halococcus
c. Staphylococcus
d. Sulfolobus
e. Methanobacterium

The human body is typically free of archaeal species.
Select one:
True
False

Which of the following bacteria is gram-negative?
Select one:
a. Corynebacterium
b. Treponema
c. Bacillus
d. Mycobacterium
e. Staphylococcus