U2 Quiz/I-Clicker Questions

Which of the following pairs of terms is mismatched?

• bacteriostatic – kills vegetative bacterial cells

• virucide – inactivates viruses

• sterilant – destroys all living microorganisms

• fungicide – kills yeasts and molds

• germicide – kills microbes

• bacteriostatic – kills vegetative bacterial cells

A(n) ________ is a bacterial virus which is integrated into the host cell DNA.

• plasmid

• lytic phage

• prophage

• transposon

• insertion phage

• prophage

A virus's ability to infect an animal cell depends primarily upon the

• presence of pili on the host cell wall.

• presence of receptor sites on the cell membrane.

• type of viral nucleic acid.

• enzymatic activity of a host cell.

• host cell's ability to phagocytize viral particles.

• presence of receptor sites on the cell membrane.

You have isolated and grown a pure culture of a prokaryotic cell type. The first step in identification is a(n)

• lactose fermentation test.

• flagella stain.

• Gram stain.

• endospore stain.

• Gram stain.

In the scientific name Enterobacter aerogenes, Enterobacter is the

• specific epithet.

• genus.

• kingdom.

• family.

• order.

• genus.

In a direct ELISA test, the method is determining if ________ is/are present in the patient's sample by attempting to bind a labeled antibody to it.

• antibodies against a pathogen found in a patient's blood

• a bacteriophage that can infect a particular bacterial strain

• an antigen from a particular pathogen

• a known sequence of DNA from a pathogen

• an antigen from a particular pathogen

The enzyme reverse transcriptase

• can synthesize DNA or RNA from an RNA template.

• synthesizes RNA from an RNA template. 

• synthesizes DNA to repair gaps in a DNA strand.

• synthesizes RNA from a DNA template.

• synthesizes DNA from an RNA template.

• synthesizes DNA from an RNA template.

An advantage of complementary DNA, cDNA, over genomic DNA is that it

• contains selectable markers.

• lacks exons 

• can form very large DNA segments.

• lacks introns.

• is very easy to isolate.

• lacks introns.

Genetic elements known as promoters are initiation points in the process of

• mutation repair.

• transcription.

• transformation.

• DNA replication.

• translation.

• transcription.

An enzyme that makes covalent bonds between Okazaki fragments in the lagging strand of DNA being replicated is

• SSBP. 

• transposase.

• DNA helicase.

• DNA ligase 

• RNA polymerase.

• DNA ligase 

Which of the following is found at the 5' end of a DNA strand?

• a hydrogen bond

• histones

• a methyl group

• a phosphate group

• a hydroxyl group

• a phosphate group

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

• desiccation

• filtration

• lyophilization

• ionizing radiation

• supercritical CO₂

• desiccation

Which of the following is the most difficult to inactivate?

• fungus spores

• nonenveloped viruses

• bacterial endospores

• protozoan cysts

• enveloped viruses

• bacterial endospores

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

• dry heat

• membrane filtration

• pasteurization

• freezing

• autoclave

• membrane filtration

A bacterial genome is typically

• multiple linear pieces of DNA.

• a single linear piece of DNA.

• multiple circular DNA molecules.

• a single circular DNA molecule.

• a linear RNA molecule.

• a single circular DNA molecule.

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

Hint: think operon regulation

• operator.

• restriction enzyme 

• repressible enzyme.

• inducible enzyme.

• promoter.

• inducible enzyme.

Which of the following is involved in translation?

• both mRNA and tRNA

• rRNA only 

• tRNA only

• mRNA only

• mRNA, rRNA, and tRNA are all involved.

• mRNA, rRNA, and tRNA are all involved.

According to the operon model, for the synthesis of an inducible enzyme to occur, the

• repressor must bind to the operator.

• repressor must not be synthesized.

• substrate must bind to the enzyme.

• end-product must not be in excess.

• substrate must bind to the repressor.

• substrate must bind to the repressor.

In Figure 8.1, which colony(ies) is/are streptomycin-resistant and valine-requiring?

• 3, 5 and 9

• 3

• 1, 2, 3, and 9

• 9

• 5

• 5

Which of the following causes mutations by creating thymine dimers?

• gamma rays

• nitrous acid

• ultraviolet light

• benzopyrene

• nucleotide analogs

• ultraviolet light

Which method of inserting DNA into cells is illustrated in Figure 8.1?

• electroporation

• injection

• transduction 

• a gene gun 

• protoplast fusion

• protoplast fusion

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

• may replicate in several species 

• self-replication

• has a selectable marker

• circular form of DNA or integrates into the host chromosome

• large size

• large size

Biotechnology involves the

• development of disease-resistant crop plants.

• use of microorganisms to make desired products.

• use of animal cells to make vaccines.

• use of microorganisms to make desired products and the use of animal cells to make vaccines. 

• use of microorganisms to make desired products, the use of animal cells to make vaccines, and the development of disease-resistant crop plants.

• use of microorganisms to make desired products, the use of animal cells to make vaccines, and the development of disease-resistant crop plants.

The natural role of restriction enzymes in bacteria is to

• allow transposons to move to another place in the chromosome. 

• allow cells to accept foreign DNA.

• protect the cell from invading phages. 

• provide the cell with new phenotypes, such as antibiotic resistance.

• make conjugation more efficient.

• protect the cell from invading phages. 

Which of the following restriction enzyme sites would produce blunt-ended fragments? (The arrow represents the cutting site of the enzyme.)

• A↓AGCTT

• CCC↓GGG 

• G↓GATCC

• C↓CGG

• G↓AATTC

• CCC↓GGG 

The phylogenetic classification of bacteria is based on _______ studies

• rRNA

• mRNA

• DNA

• tRNA

• ribosomal RNA (rRNA) sequences.

Which of the following is the best evidence for a three-domain system?

• There are three distinctly different types of nuclei. 

• Some bacteria live in extreme environments.

• There are three distinctly different Gram reactions.

• Nucleotide sequences in ribosomal RNA vary between all three domains.

• There are three distinctly different sets of metabolic reactions.

• Nucleotide sequences in ribosomal RNA vary between all three domains.

A biochemical test, in the microbiology world, is used to determine

• All of the answers are correct. 

• staining characteristics.

• nucleic acid-base composition of DNA sequences.

• amino acid sequences of enzymes.

• capability of a microbe to perform a specific enzymatic activity.

• capability of a microbe to perform a specific enzymatic activity.

What is the outstanding characteristic of the Kingdom Fungi?

• All members are photosynthetic (phototrophs)

• All members are macroscopic. 

• Members absorb dissolved organic matter. (chemo- or photo-heterotrophs) 

• All members are microscopic.

• Members absorb dissolved organic matter. (chemo- or photo-heterotrophs) 

In Table 10.1, which features are found in nearly all eukarya?

• 3, 5

• 2, 3

• 1, 2, 5

• 1, 4, 6

• 2, 3, 5

• 2, 3, 5

Assume 109 E. coli cells/ml are in a flask. Which graph in Figure 7.2 best depicts the effect of placing the culture at 7°C at time x?

• e

• d

• c

• b

• a

• d

Seventy percent alcohol is effective against

• enveloped viruses

• protozoan cysts

• bacterial endospores

• nonenveloped viruses

• prions

• enveloped viruses

A chemical agent that dissolves lipids can damage

• enveloped viruses.

• cells.

• cells and enveloped viruses.

• bacterial endospores.

• nonenveloped and enveloped viruses.

• cells and enveloped viruses.

The following data were obtained by incubating gram-positive bacteria in nutrient medium + disinfectant for 24 hours, then transferring one loopful to nutrient medium (subculturing). (+ = growth; - = no growth)
In Table 7.3, which disinfectant was bactericidal?

• Doom

• Sterl

• The answer cannot be determined based on the information provided.

• Mortum

• K.O.

• Mortum

In Figure 8.5, which model of the lac operon correctly shows RNA polymerase, lactose, and repressor protein when the structural genes are being transcribed?

• b

• a

• e

• d

• c

• d

Two bacterial strains have the same genes for metabolizing a carbohydrate, but one is wild-type for a regulatory inducer while the other does not produce the inducer. Which of the following statements is CORRECT with regard to the metabolism of the bacteria?

• The two bacterial strains have the same phenotype.

• The genotypes and phenotypes of the two bacterial strains are the same.

• The two bacterial strains have the same phenotype but have different genotypes.

• The two bacterial strains have different phenotypes.

• The answer cannot be determined from the information provided.

• The two bacterial strains have different phenotypes.

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

• have exons.

• require snRNPS

• use codons to determine polypeptide sequences.

• use methionine as the "start" amino acid.

• have introns.

• use codons to determine polypeptide sequences.

Which of the following pairs is mismatched?

• RNA polymerase - makes a molecule of RNA from an RNA template

• DNA ligase - joins segments of DNA

• DNA polymerase - makes a molecule of DNA from a DNA template

• transposase - cuts DNA backbone, leaving "sticky ends"

• DNA gyrase - relaxes supercoiling in DNA ahead of the replication fork

• RNA polymerase - makes a molecule of RNA from an RNA template

The horizontal transfer process known as transduction

• requires a plasmid.

• involves a virus.

• involves a mutagen.

• requires a cell to be "competent."

• requires a pilus

• involves a virus.

Amino acids are delivered in their appropriate order by

• ribozymes.

• mRNAs.

• rRNAs.

• RNA-induced silencing complexes (RISC).

• tRNAs.

• tRNAs.

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

• form blue, ampicillin-sensitive colonies.

• not grow.

• form blue, ampicillin-resistant colonies.

• form white, ampicillin-resistant colonies.

• form white, ampicillin-sensitive colonies.

• form white, ampicillin-resistant colonies.

________ are used for cutting DNA molecules into fragments.

• Antisense RNAs

• Mutagens

• DNA polymerase and DNA ligase

• RNA polymerases

• Restriction enzymes

• Restriction enzymes

Which of the following microbes produces a protein that kills a variety of insect pests? [Hint: insects are a pest for plants]

• Pseudomonas

• Haemophilus influenzae

• Thermus aquaticus

• Plasmodium falciparum

• Bacillus thuringiensis

• Bacillus thuringiensis

When performing phage typing to identify an unknown bacterium, you must have ________ in your possession.

• fluorescent molecules that will light up when bound to the DNA of the bacterium

• antiserum containing antibodies that will bind to the bacterium to be identified

• DNA that will hybridize to the DNA of the bacterium to be identified

• RNA that will hybridize to the RNA of the bacterium to be identified

• viruses that will specifically infect the bacterium you're trying to identify

• viruses that will specifically infect the bacterium you're trying to identify

You discovered a unicellular organism that lacks a nucleus and peptidoglycan. You suspect the organism is in the group

• Fungi.

• Bacteria.

• Animalia.

• Plantae.

• Archaea.

• Archaea

For a serological bacterial identification test to be performed, you must have ________ in your possession.

• RNA that will hybridize to the RNA of the bacterium to be identified

• viruses that will specifically infect the bacterium you're trying to identify

• fluorescent molecules that will light up when bound to the DNA of the bacterium

• DNA that will hybridize to the DNA of the bacterium to be identified

• antiserum containing antibodies that will bind to the bacterium to be identified

• antiserum containing antibodies that will bind to the bacterium to be identified

Serological testing is based on the fact that

• antibodies react specifically with an antigen.

• antibodies cause the formation of antigens.

• bacteria clump together when mixed with any antibodies.

• all bacteria have the same antigens.

• the human body makes antibodies against bacteria

• antibodies react specifically with an antigen.

If two organisms have similar ribosomal RNA (rRNA) sequences, you can conclude that they

• mated with each other.

• will have different G-C ratios.

• live in the same place.

• evolved from a common ancestor.

• will both ferment lactose.

• evolved from a common ancestor.

Which of the following does NOT achieve sterilization?

• Autoclaving at 121°C for 15 minutes

• Dry heat at 170°C for 2 hours

• Ethylene oxide gas treatment

• Pasteurization

• Ionizing radiation

Pasteurization

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

Doom

Which of the following is an example of pasteurization?

• Heat is used to kill potential pathogens in apple juice.

• Surgical instruments are autoclaved at 121°C for 15 minutes.

• Bacterial cultures are incinerated after use.

• A 0.22 µm membrane filter is used to sterilize a solution.

• Canned food is heated under pressure to destroy endospores.

Heat is used to kill potential pathogens in apple juice.

A gene is defined as

• a sequence of nucleotides in DNA that codes for a functional product.

• Any region of DNA between two promoters.

• A sequence of amino acids that forms a protein.

• A DNA segment that always codes for a protein

• A nucleotide sequence that contains only exons.

a sequence of nucleotides in DNA that codes for a functional product.

Which of the following is NOT a product of transcription?

• mRNA

• tRNA

• rRNA

• A new strand of DNA

a new strand of DNA.

DNA is constructed of

• Two strands of amino acids arranged in a double helix

• A single strand of nucleotides folded into a helix

• Two parallel strands of nucleotides running in the same 5′ → 3′ direction

• Two strands of nucleotides running in an antiparallel configuration

two strands of nucleotides running in an antiparallel configuration.

A bacterial genome is typically

• Multiple linear chromosomes enclosed in a nuclear membrane

• A single circular DNA molecule

• Several circular chromosomes housed in a nucleus

• A linear double-stranded DNA molecule with telomeres

a single circular DNA molecule.

The ozone layer of the Earth has been depleted to an extent by human release of certain chemicals. What type of mutation caused by the induction of thymine dimer formation is more likely to occur in organisms on Earth as a result of this problem?

• Missense mutation

• Silent Mutation

• Frameshift mutation

• Nonsense mutation

frameshift mutation.

Double strand DNA fragments are separated by size using

• Polymerase chain reaction (PCR)

• DNA ligase

• Peptide bonds

• Gel electrophoresis

gel electrophoresis

The restriction enzyme EcoRI recognizes the sequence G↓AATTC. Which of the following is TRUE of DNA after it is treated with EcoRI?

• All fragments will have blunt ends.

• All fragments will have single-stranded regions ending in TT.

• The DNA will be completely degraded into single nucleotides.

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

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

________ are a diverse group of eukaryotic organisms that are similar in ribosomal RNA (rRNA) sequences but quite different from each other in motility types and ecology. They have been used previously as a "catch-all" for organisms that couldn't be easily classified into other groups.

• Archea

• Bacteria

• Protists

• Fungi

• Protists.

What is the outstanding characteristic of the Kingdom Fungi?

• Members perform photosynthesis using chlorophyll.

• Members ingest food particles by phagocytosis.

• Members are primarily autotrophic and fix carbon dioxide.

• Members absorb dissolved organic matter (chemo- or photo-heterotrophs).

Members absorb dissolved organic matter (chemo- or photo-heterotrophs).

Use the dichotomous key in Table 10.2 to identify a gram-negative coccus.

• Neisseria

• Citrobacter

• Micrococcus

• Salmonella

Neisseria.

In Figure 10.1 the closest ancestor for both species "a." and species "b." would be which of the following?

• 4

• 1

• 3

• 5

5

A group of three nucleotides on mRNA is called an

• operon

• codon

• amino acid

• RNA polymerase

codon

Transcription begins when RNA polymerase binds to the DNA at the

• promoter

• inducer

• repressor

• DNA Polymerase

promoter

Of the 64 codons how many are sense codons

• 30

• 61

• 24

• 60

61

Between 60% and 80% of genes are not regulated by the cell but are ___________ in nature

• Inducible

• Repressible

• Operonic

• Constitutive

Constitutive

What is the process that turns ON the transcription of a gene or genes?

• polymerase chain reaction

• repressor

• induction

• promoter

Induction

A group of genes that are transcribed together and controlled by one promoter defines a

• amino acid sequence

• operon

• promoter

• repressor

operon

Inhibition of the metabolism of alternative carbon sources by glucose is called

• Competitive inhibition

• Feedback inhibition

• Induction

• Catabolite repression

catabolite repression

Single stranded RNA molecules that inhibit protein production in eukaryotic cells are known as

• tRNA

• mRNA

• miRNA

• rRNA

microRNAs (miRNAs)

Ionizing radiation causes

• DNA polymerase reaction

• RNA polymerase reaction

• DNA strand breaks

• amino acids break

DNA strand breaks

What is the most common type of mutation which involves single base pairs?

• frameshift mutation

• missense mutation

• base substitution

• silent mutation

base substitution

The process of bacteria passing their genes to other microbes of the same generation is known as

• vertical gene transfer

• horizontal gene transfer

• diagonal gene transfer

• rapid gene transfer

horizontal gene transfer

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

• Direct cell-to-cell contact through a pilus

• A bacteriophage vector

• Membrane-bound vesicles

• Naked DNA in a solution

naked DNA in a solution

A population of genetically identical cells carrying a desired vector is called a

• clone

• operon

• amino acid

• gene

clone

In nature organisms with characteristics that enhance survival are more likely to survive and reproduce than variants that lack desirable traits this is known as

• Genetic drift

• Mutation

• Artificial selection

• Natural selection

natural selection

A DNA molecule that transports foreign DNA into a cell is called a

• operon

• vector

• amino acid

• gene

vector

Which technique amplifies small samples of DNA to quantities that are large enough for analysis

• Gel electrophoresis

• DNA sequencing

• Restriction enzyme digestion

• Polymerase Chain Reaction (PCR)

PCR (polymerase chain reaction)

The technique that separates DNA fragments of different lengths by applying a charge is known as

• covalent bonds

• peptide bonds

• gel electrophorensis

• ionic bonds

gel electrophoresis

If a restriction enzyme makes a staggered cut in DNA then ____________ asymmetrical ends are created

• blunt

• sticky

• slimy

• hard

sticky

A molecular clock for evolution is based on

• Fossil record comparisons

• Morphological similarities between species

• Protein shape and structure differences

• Nucleotide sequences in the genomes of organisms

nucleotide sequences in the genomes of organisms

Which is the correct order in the taxonomic hierarchy from the broadest to most specific

• Kingdom-phylum-class-order-family-genus-species

• Phylum-kingdom-order-genus-family-species

• Order-family-species-kingdom-phylum-class

• Phylum-order-class-species-genus-family

Kingdom-phylum-class-order-family-genus-species

All proteobacteria are

• Gram-positive bacteria

• Obligate intracellular parasites

• Photosynthetic autotrophs

• Oligotrophs

Oligotrophs

Which of the following refers to photosynthesis preformed by bacteria with the use of water as the donor of electrons

• Anoxygenic

• Chemolithotrophic

• Photophosphorylation

• Oxygenic

oxygenic

Which of the following bacteria lacks a cell wall?

• Myxococcus

• Fungi

• Mycoplasma

• Bacteria

Mycoplasma

Which one of the following is NOT a category of Archea

• Methanogens

• Extreme halophiles

• Thermoacidophiles

• Low G+C gram-positive rods and cocci

Low G+C gram-positive rods and cocci

Nitrogen-fixing bacteria that infect the roots of leguminous plants are known as

• Cyanobacteria

• Azotobacter

• Mycorrhizae

• Rhizobia

rhizobia

Unicellular algae with complex cell walls made of pectin and a layer of silica

• Dinoflagellates

• Green algae

• Cyanobacteria

• Diatoms

diatoms

The body of a multicellular algae is called a

• Mycelium

• Hypha

• Sporophyte

• Thallus

thallus

The largest bacterium discovered found in sediments of the costal waters off Namibia belongs to the genus

• Beggiatoa

• Spirillum

• Nitrobacter

• Thiomargarita

Thiomargarita

Nitrosomonas and Nitrobacter play a role in the nitrogen cycle by conducting

• Nitrogen fixation

• Denitrification

• Ammonification

• Nitrification

nitrification

Alphaproteobacteria often have stalklike or budlike protrusions known as

• Flagella

• Pili

• Hyphae

• Prosthecae

prosthecae

Which of the following is NOT a member of the order Enterobacteriales

• Escherichia

• Salmonella

• Klebsiella

• Pseudomonas

Pseudomonas

The common infectious genus in the world which only lives inside the cells of insects is

• Rickettsia

• Ehrlichia

• Bartonella

• Wolbachia

wolbachia

In which phylum has sexual reproduction NOT been observed

• Ascomycota

• Basidiomycota

• Zygomycota

• Microsporidia

Microsporidia

The phylogenetic relationship among proteobacteria is based on ___________ studies

• rRNA

• tRNA

• mRNA

• miRNA

rRNA

Paralytic shellfish poisoning is caused by dinoflagellates that secrete a neurotoxin known as

• Tetrodotoxin

• Botulinum toxin

• Anatoxin

• Saxitoxin

saxitoxin

Taq polymerase an enzyme used in PCR is derived from Thermus aquaticus which belongs to which bacterial phylum

• Proteobacteria

• Firmicutes

• Cyanobacteria

• Deinococci

deinococci

Elementary bodies are found in the phylum

• Rickettsiae

• Spirochaetes

• Firmicutes

• Chlamydiae

Chlamydiae

The enzymes that fix nitrogen gas into ammonium in cyanobacteria are located in

• Carboxysomes

• Akinetes

• Thylakoids

• Heterocysts

heterocysts