BMSC 210 PRACTICE FINAL Flashcards
The ability of humans to resist a disease is called
Immunity
Pattern recognition receptors (PRRs) are found on which of the following cells?
Macrophages and neutrophils
Adaptive immune responses are directed at pathogen molecules called
antigens
An example of a pathogen-associated molecular pattern (PAMP) is
lipopolysaccharide (LPS)
Adaptive immunity occurs when
the innate immune response fails to eliminate pathogens in the body and virulent infections persist after the initial innate defense response
The pathogen-associated molecular pattern (PAMP) recognized by mannose-binding lectin (MBL) isthe sugar mannose, found as a repeating subunit in
bacterial polysaccharides
________ are cytotoxins produced by T cells that cause apoptosis
Granzymes
T cells recognize antigens with their
T cell receptors
________ is a group of sequentially interacting proteins important in innate and adaptive immunity.
complement
The part of the antigen recognized by the antibody or TCR is called the
epitope
Unactivated dendritic cells act as antigen presenting cells for which of the following T cell subsets?
Treg only
Which of the following T cell subsets is a CD8 T cell?
a) Th2 b) Treg c) None of these. d) Th17
None of the above
Proteins derived from infecting viruses are taken up and digested in the cytoplasm in a structure called the
proteasome
Antigen-presenting cells present antigens to
T lymphocytes
T or F: Th2 cells produce a cytokine that promotes growth and activation of other T cells and activates macrophage
False
The cells active in both innate and adaptive immunity develop from common pluripotent precursorsin the bone marrow called
stem cells
The body’s noninducible, preexisting ability to recognize and destroy a variety of pathogens or theirproducts is called
innate immunity.
Antibodies are found in
milk, mucosal secretions, and serum
Enhanced phagocytosis of antibody-sensitized cells is known as
opsonization
Substances that induce an immune response are known as
Immunogens
Th cells express a ________ protein coreceptor.
CD4
Intrinsic properties of immunogens include
appropriate physical form, molecular size, and molecular complexity
Communication between cells of the immune system is accomplished in many cases through
cytokines
The first defense cells that interact with a pathogen in the body are
macrophages
T or F: Helicobacter pylori, when present, is the MOST common single organism found in the stomach.
True
Which of the following is NOT found in the gastrointestinal tract of a healthy individual?
protists
Which of the following is NOT produced by microorganisms in the gut of humans?
Vitamin C
Bacteria make up about ____________ the weight of fecal matter
One-third
Which of the following will happen after a person takes an antibiotic orally?
A) All of the other answers b) The growth of normal flora will be inhibited c) Opportunistic microorganisms such as antibiotic resistant Staphylococcus aureas may become established d) The growth of pathogens will be inhibited
A) all of the other answers
Saliva is a poor growth medium for bacteria due to
the presence of lysozyme
The lower respiratory tract does not have any resident microbial flora
because most organisms are too small to make it to the bronchi
because organisms settle out of the air prior to reaching the trachea
The variety of microenvironments on the skin allows the skin to have
a large diversity of the microbiome
Gut colonizers are an important source of
amino acids
vitamin K
B vitamins
The most stable gut species include
Bacteroides
Knowing specifics of a person’s microbiome can potentially lead to
targeted treatment for disease
personalized drug therapies
probiotics made that just target specific imbalances
___________ is the growth of microorganisms NOT normally present within a host
Infection
Following exposure to a pathogen, events leading to disease—in the correct order— are
adherence, invasion, infection, toxicity
Adherence factors include ALL of the following EXCEPT
lipopolysaccharide layers
Growth of a microorganism after entering a host is called
colonization
Which of the following does NOT occur during the development of dental caries?
Oral microflora produce high concentrations of exoenzymes when sucrose is present
The ability of a pathogen to enter a cell, spread, and cause disease is termed
invasion
A bacterial infection becomes a disease when
there is tissue damage that impairs host function
_____________can vary between strains of an organism depending on the ability to adhere, colonize, and invade a host
Virulence
___________organisms are valuable in the production of vaccines
Attenuated
Organism X has an L D50 of 2 × 102, and organism Y has an L D50 of 3 × 104. Which organism is more virulent
organism X
Which of the following environmental and host factors influence the composition of the resident microbiota on the skin?
age. personal hygiene and weather
Which of the following is TRUE about research on the human microbiome?
Advanced nucleic acid sequencing techniques were needed before a good understanding of its microbial abundance and diversity could be developed
Which of the following is NOT a major question in the Human Microbiome Project?
How can we reduce the number of microbes on the human body?
The damaged areas of teeth caused by organic acids produced by dental plaque are called
dental caries
Normal microbiota helps to ________ colonization of pathogenic organisms
prevent
Which of these microorganisms is most likely to be found in the human stomach?
Helicobacter pylor
Which of the following is NOT true of human gut microbes?
Which of the following is NOT true of human gut microbes?
Lysozyme is found throughout our bodies to protect us from infection. Some bacteria can evade this defense
by altering their peptidoglycan
Because they are Gram negative, E. coli, Salmonella, and Shigella all produce
endotoxins
Which of the following toxins is NOT a cytolytic exotoxin?
Shiga toxin
Genes for antiphagocytic proteins, exotoxins, and adherence that are clustered together on a bacterial chromosome are called
pathogenicity islands
All of the following are enzymes that increase virulence EXCEPT
cellulase
Diphtheria toxin is
an AB toxin
Pathogens that can secrete ______________ are more virulent because of the organism’s potential to spread in the host
hyaluronidase
Exotoxins classified as AB toxins damage cells by
using the B subunit to attach to the target cell while the A subunit enters and inhibits protein synthesis
The host-microbiome supraorganism refers to
a body and all of its associated microbes
The human oral microbiota consists of
diverse aerobic and anaerobic microorganisms
The vagina of an adult female is
weakly acidic
T or F: Endotoxins are the secreted products of living cells, whereas exotoxins are cell bound and released in large amounts ONLY when the cells lyse
False
Streptokinase works to ___________ fibrin clots while coagulase works to ___________ fibrin clots
dissolve / promote
Healthcare-associated infections (HAI s) are also called
nosocomial infections
Which of the following has the highest level of containment and is where drug-resistant Mycobacterium tuberculosis must be studied
BSL-4
The antimicrobial susceptibility of a bacterium can be determined by
the tube dilution technique
the disk diffusion test
determining the minimum inhibitory concentration
Media that can differentiate organisms based on colony appearance are
differential
Aseptic technique in obtaining clinical specimens is essential to ensure bacterial presence is due only to
infection
T or F: If an individual is infected with a pathogen, the antibody titer to that pathogen will decrease
False
Advantages of qPCR tests over traditional end-point PCR tests include
eliminating the need for agarose gel electrophoresis
continuous monitoring
determining the amount of target DNA present in an original sample
In the triple sugar iron test the reaction of hydrogen sulphide produced by bacteria with ferrous ironin the medium produces
blackening of the agar
Thayer Martin medium is a selective medium used for the clinical isolation of
Neisseria gonorrhoeae
Beta hemolysis on blood agar indicates
complete hemolysis
In a dipstick nucleic acid assay, dual reporter and capture probes are used. The capture probe
binds to the dipstick
During an infection with Salmonella enterica Serovar Typhi (typhoid fever) as the antibody titre increases
bacteria are cleared from the blood
T or F: Monoclonal antibodies are directed to a number of different epitopes on a bacterial antigen
False
In a passive (indirect) agglutination test
antibodies or antigens are absorbed or chemically coupled to cells or insoluble particles such as latex beads
A Western blot usually involves
protein
For a disease to become a pandemic, it must
initially start out as an epidemic and have widespread infections
The incidence of BOTH fatal and nonfatal diseases in a population is called
morbidity
An endemic disease
is constantly present in the populace
The prevalence of a disease is
the total number of both new and existing cases
A disease that primarily infects an animal but is occasionally transmitted to humans is called a(n)
zoonosis
Carriers contribute to the spread of which of the following diseases?
HIV
Typhoid fever
Hepatitis
A disease outbreak that has a large number of cases diagnosed in a very short period time is characteristic of
a common source epidemic
COVID-19 is primarily transmitted through
aerosol droplet spread
The region of the world with the highest burden of disease as measured by DALYs is
sub-Saharan Africa
If the reproduction number for COVID-19 is >1, that means that
each existing infection causes more than one new infection possibly leading to an outbreak
The basis for blood typing is referred to as
hemagglutination
T or F: some infectious agents, such as Neisseria gonorrhoeae, do NOT elicit a systemic immune response
True
Laboratories that work with extremely low risk pathogens are classified as
BSL-1
Antibody titer can be measured by
agglutination
Indirect EIA is used to detect
antibodies
Which of the following immunological tests would allow the specific identification of a microorganism directly in infected tissues?
Fluorescent antibody (FA)
SYBR Green, commonly used in qPCR, binds nonspecifically to ________, indicating the presence of the PCR product
dsDNA
A disease that is present in unusually high numbers throughout the world is called
a pandemic
Answer
host-to-host epidemic.
The basic reproduction number of a pathogen such as SARS-CoV-2 (causes COVID-19)
can vary during an epidemic based on infection control measures
Disease ________ is measured by the total number of new reported disease cases within a population over a period of time
incidence
An inanimate object that transmits infectious agents between hosts is most appropriately called a
fomite
Which of the following is an example of herd immunity
If 70% of the population is immunized against polio, the disease will be essentially absent from the population
Typhoid Mary is an example of a ________, because she was infected by the causative agent ʺ ʺfor typhoid fever yet was asymptomatic
carrier
You are an epidemiologist analyzing the onset of a given epidemic and note that the epidemic is indicated by a notable sharp rise in the number of cases reported daily over a brief interval. This indicates that the mode of transmission is
common source
T or F: A disease that is constantly present in low numbers is called an acute disease.
False
In Ontario and many other provinces, the number of cases of COVID-19 is increasing and authorities are concerned because the reproduction number indicates transmission to multiple people. In this case the R0 number would be
> 1
The blotting of proteins from polyacrylamide gels to nitrocellulose paper, and the subsequent identification by specific antibodies, is called a(n) ________ blot
Western
MacConkey agar and eosin-methylene blue (EMB) agar are ________ media
both selective and differential
An Etest® is a clinical tool used for the determination of
he minimum inhibitory concentration (MIC) value of an antimicrobial agent
The most prevalent STI globally is
Chlamydia trachomatis
Neisseria gonorrhoeae is a
Gram-negative diplococcus
The current treatment for gonorrhea is
Combination therapy with ceftriaxone and azithromycin
Gonorrhea can be diagnosed by
Gram stain, esp in men
Biochemical tests
nucleic acid amplification tests
If a chancre forms on your body, what disease would you likely have
syphilis
What is a typical symptom of secondary syphilis
generalized skin rash
Which drugs would you use to treat penicillin-resistant Neisseria gonorrhoeae?
ceftriaxone plus azithromycin
Kaposi’s sarcoma causes cancer of the cells lining the blood vessels, which forms purple splotcheson the skin and occurs during co-infection of HIV and
human herpesvirus 8
T or F: There are safe and effective HIV-2 vaccines available, but because HIV-1 has such high genetic variability, the vaccines are of little use to prevent AIDS
True
HIV-1
targets T-helper cells
argets macrophage
is a retrovirus
The CD4 cell surface protein binds to which HIV protein(s)
gp120.gp41
Is it possible for humans to have immunity to HIV infections and, if so, how?
Yes, by expressing a non-HIV binding variant of CCR5
HPV is a
virus
T or F: Upper respiratory pathogens are generally more deadly than lower respiratory pathogens
False
Destroyed tissue throughout the lungs and the presence of acid-fast bacteria in a sputum sample likely indicate infection by
Mycobacterium tuberculosis
a pseudomembrane is found in cases of
Diphtheria
Diphtheria is caused by strains of C. diphtheriae which are ________
lysogenized by bacteriophage B
T or F: Mycobacteria are acid-fast
True
Neisseria meningitidis belongs to the phylum
Proteobacteria
Which of the following diseases is NOT caused by an airborne virus?
scarlet fever
Why should pregnant women NOT be immunized with the rubella vaccine?
Rubella virus can infect the fetus by placental transmission and cause serious fetal abnormalities
Varicella-zoster virus (VZV) causes which disease
chicken pox
Which symptom below does NOT correctly distinguish a cold from influenza (respectively)
malaise: common / rare
Reassortment of a virus that results in antigenic shift most commonly occurs in
any animal infected with more than one virus strain
The Ebola virus targets cells of the
liver and spleen
Although a nonhuman reservoir for Helicobacter pylori has not been identified, it is considered a direct contact disease because
it occurs in clusters and predominates in families
Lyme disease can be transmitted by being bitten by an
infected tick
A characteristic symptom of Lyme disease is
a bull’s eye rash
Plague, also known as the Black death is caused by
a bacterium
T or F: the rat flea Zenopsylla cheopsis carries cells of Yersinia pestis
True
The reticulate body (RB) of C. trachomatis
is intracellular
Lymphogranuloma venereum is a sexually transmitted disease caused by distinct strains of
Chlamydia trachomatis
N. gonorrhoeae infections can be diagnosed by
Gram stain esp in male urethral specimens
PCR
biochemical tests
The recommended treatment for infections with Neisseria gonorrhoeae is
ceftriaxone plus azithromycin
Tertiary syphilis
can be manifested in neurological and cardiovascular complications
Which of the following does NOT apply to bacterial pathogens affecting the respiratory tract?
Most respiratory bacterial pathogens do not respond to antibiotic therapy.
The causative agent of streptococcal pharyngitis, also known as strep throat, is
Streptococcus pyogenes
The pathogenicity of strains of Streptococcus pneumoniae is because they
carry an antiphagocytic capsule
T or F: Infections by flesh-eating bacteria can occur when exotoxins A, B, C, and F and the bacterial ʺ ʺsurface M protein of Streptococcus pyogenes act as superantigens
True
Which of the following microbial groups is most resistant to desiccation due to their cell wall?
Gram-positive
Shingles is caused by latent
varicella-zoster virus
The primary disease reservoir for plague is
rats
The MMR vaccine comprises
Attenuated live virus
In bubonic plague, buboes are swellings formed in the lymph nodes and filled with
plague
The disease whose symptoms are most closely related to the symptoms of chronic syphilis is
chronic Lyme disease
Thayer Martin medium is used for growing
Neisseria gonorrhoea
Once a person has been infected with Neisseria gonorrhoeae, the individual
can be reinfected immediately because of the diversity of strains and frequency of mutation
Risks for acquiring a sexually transmitted infection do NOT include
using condoms
Which of the following is TRUE of tuberculosis
The causative agent can remain dormant in macrophages
Loeffler’s medium inhibits the growth of most organisms and is commonly used to cultivate
Corynebacterium diphtheriae
T or F: The immune response may be as important as antibiotics in the elimination of Bordetella pertussisfrom the body
True
Minor changes in influenza virus antigens due to gene mutations is known as
antigenic drift
Murine toxin is a ________ that is a respiratory inhibitor and lethal to mice.
Yersinia pestis exotoxin
A positive tuberculin test means a patient
may have active disease, been previously exposed to Mycobacterium tuberculosis, or may have a current inapparent infection
Colds are mostly caused by
rhinoviruses
Impetigo is due to an infection caused by
either Staphylococcus aureus or Streptococcus pyogenes
T or F: Reassortment of the genes of the influenza virus is facilitated by the fact that the genome is segmented
True
Which of the following statements about chlamydial infections is TRUE
Chlamydial diseases can lead to acute complications
Influenza A virus can be identified by which of the following surface glycoproteins?
Both HA and NA
Which method would be the MOST powerful approach to isolating a single mutant from a population of billions?
a) replica plating
b) assay for the loss of function
c) selection for a gain of function
d) screen for the mutant
selection for a gain of function
Which of the following can restore a frameshift mutation?a) another frameshift, microdeletion, and microinsertion
b) microinsertion
c) microdeletion
d) another frameshift
another frameshift, microdeletion, and microinsertion
Consider a mutation in which the change is from UAC to UAU. Both codons specify the amino acid tyrosine. Which type of point mutation is this?
a) Silent mutation
b) Missense mutation
c) Nonsense mutation
d) Frameshift mutation
Silent mutation
Nutritionally defective mutants can be detected by the technique of
a) transversion.
b) replica plating.
c) transposon mutagenesis.
d) selection
b) replica plating.
A mutation in a particular gene that results in the premature halting of transcription (and, consequently, protein translation) is a___________ mutation.
a) transition
b) complementary
c) nonsense
d) missense
c) nonsense
A mutant that has a nutritional requirement for growth is an example of a(n)
a) auxotroph
.b) organotroph.
c) heterotroph.
d) autotroph
a) auxotroph
Second-site mutations that compensate for the effects of another mutation are known as
a) transversions.
b) transitions.
c) frameshift mutations.
d) suppressor mutations
d) suppressor mutations
You work for a biotechnology company that uses Streptomyces strains to produce pharmaceutical products. A phage has infected and killed some of your Streptomyces strains during production, resulting in dramatically decreased yields. To protect the strains from infection you propose to
a) transform the Streptomyces strains with plasmids encoding antibody proteins that will protect them from phage infection.
b) infect the Streptomyces strains with a helper phage that will help the strains resist infection.
c) introduce gene transfer agents into the Streptomyces cultures to transfer antibiotic resistance genes into your Streptomyces strains.
d) design and insert CRISPR spacer sequences into the genomes of your strains that are complementary to the genomes of the phages that are infecting the cultures
d) design and insert CRISPR spacer sequences into the genomes of your strains that are complementary to the genomes of the phages that are infecting the culture
The conversion of non-toxin-producing strains of Corynebacterium diphtheriae to toxin-producing (pathogenic) strains following lysogeny with phage is an example of
a) phage conversion.
b) transduction.
c) transposition.
d) lysogeny switching
a) phage conversion.
F+ strains of Escherichia coli
a) transfer the F factor to recipient cells at a high frequency.
b) do not have an F factor.
c) have the F factor as a plasmid.
d) have an integrated F factor.
c) have the F factor as a plasmid
The uptake of free DNA from the environment is referred to as ________, while the transfer of DNA with cell-to-cell contact is known as ________
a) transformation / conjugation
When DNA is transferred into a prokaryotic cell, it may
a) replicate independent of the host chromosome
.b) recombine with the host chromosome.
c) be degraded by enzymes.
d) be degraded by enzymes, replicate independent of the host chromosome, or recombine with the host chromosome
d) be degraded by enzymes, replicate independent of the host chromosome, or recombine with the host chromosome
A plasmid may
a) replicate independently of the chromosome, integrate into the chromosome, or be transferred cell-to-cell during conjugation.
b) replicate independently of the chromosome.
c) be transferred cell-to-cell during conjugation.
d) be integrated into the chromosome
a) replicate independently of the chromosome, integrate into the chromosome, or be transferred cell-to-cell during conjugation.
Consider the following experiment. First, large populations of two mutant strains of Escherichia coli are mixed, each requiring a different, single amino acid. After plating them onto a minimal medium, 45 colonies grew. Which of the following may explain this result?
A) The colonies may be due to back mutation (reversion).
B) The colonies may be due to recombination.
a) B only
b) A only
c) Either A or B is possible
d) Neither A nor B is possible
c) Either A or B is possible
The F (fertility) plasmid contains a set of genes that encode for the ________ proteins that are essential in conjugative transfer of DNA.
a) SOS repair
b) pili
c) transduction
d) transformation
b) pili
A point mutation refers to mutations involvingʺ ʺ
a) the gain of a base pair (microinsertion).
b) a substitution, deletion, or addition of one base-pair.
c) the deletion of a base pair (microdeletion).
d) a base-pair substitution
a substitution, deletion, or addition of one base-pair
Microinsertions and microdeletions often result in ________ mutations.
a) frameshift
b) auxotrophic
c) advantageous
d) silent
frameshift
Which of the following methods may introduce foreign DNA into a recipient?
a) Conjugation
b) Transformation, transduction, and conjugation
c) Transformation
d) Transduction
b) Transformation, transduction, and conjugation
The CRISPR system
a) repairs DNA and increases DNA damage tolerance during times of stress.
b) facilitates homologous recombination through a complex system of proteins and clustered repeats.
c) recognizes foreign DNA sequences that have previously entered the cell and directs the Cas proteins to destroy them.
d) synthesizes gene transfer agents during stationary phase.
recognizes foreign DNA sequences that have previously entered the cell and directs the Cas proteins to destroy them.
Lysogeny probably carries a strong selective advantage for the host cell because it
a) confers resistance to infection by viruses of the same type.
b) confers resistance to infection by many virus types and prevent cell lysis.
c) confers resistance to infection by viruses of a different type (or strain).
d) prevents cell lysis
confers resistance to infection by viruses of the same type
Which is NOT true about PCR?a) It uses oligonucleotide primers that are complementary to the flanking regions of target DNA
b) It amplifies DNA sequences
c) It is used for making DNA for cloning and DNA sequencing
d) It uses DNA polymerases from psychrophilic microbes
d) It uses DNA polymerases from psychrophilic microbes
If you wanted to compare the relative abundance of mRNA transcribed for a specific gene by two different strains of bacteria, you would perform a) a Northern blot
b) a Southern blot
c) site directed mutagenesis
d) a blot identifying proteins
Northern blot
27) Nucleic acid probes comprise
a) proteins which bind to DNA at specific regions
b) ss DNA fragments complementary to the sequence of interest
c) None of the other answers
d) DS DNA fragments complementary to the sequence of interes
b) ss DNA fragments complementary to the sequence of interest
Cutting DNA with EcoR1 will produce
a) 3’ overhangs
b) a mixture of blunt ends and 5’overhangs
c) blunt ends
d) 5’ overhangs
5’ overhands
Genetic engineering requires
a) a cloning vector and a host for expression
b) a vector and a host for gene expression
c) various genetic building blocks and a host for expression
d) various genetic building blocks, a cloning vector and a host for expression
various genetic building blocks, a cloning vector and a host for expression
During gene cloning, the vector and the foreign DNA are cleaved ________ restriction enzyme(s) and then are joined ________.
a) the same/ DNA polymerase
b) the same / DNA ligase
c) different/ DNA ligase
d) different/ DNA polymerase
b) the same / DNA ligase
What is NOT true regarding the use of yeast artificial chromosomes (YACs) for cloning?
a) They are circular vectors
b) They contain a gene for selection
c) Large fragments of DNA can be inserted into them
d) They have features to allow them to replicate and segregate like normal eukaryotic chromosomes
They are circular vectors
When using a reporter gene to investigate expression of a target protein, the promoter of _________ is ligated to the coding sequence of the ____________.
a) green fluorescent protein / lacZ
b) reporter gene / target gene
c) target gene / reporter gene
d) lacZ / green fluorescent protein
c) target gene / reporter gene
The synthetic molecule used in CRISPR gene editing is
a) Cys4
b) Cas9
c) synthetic guide RNA (sgRNA).
d) protospacer adjacent motif (PAM)
synthetic guide RNA (sgRNA)
Escherichia coli is naturally transformable
a) True
b) False
False
What is referred to as “microbial dark matter?”
a) Comprehensive models for predicting the behavior or properties of an organism
b) Contaminants found in samples prepared for genomic sequencing
c) Prokaryotic organisms that are detected in environmental16S rRNA gene surveys but for which no laboratory cultures are available
d) Microbes that evade the immune system
c) Prokaryotic organisms that are detected in environmental16S rRNA gene surveys but for which no laboratory cultures are available
Which type of analysis is typically used for proteomics?a) Mass spectrometry
b) RNA-Seq
c) MDA -multiple displacements amplification
d) Microarrays
a) Mass spectrometry
MDA, used in single cell genomics, requires
a) NIMS technology
b) a unique protease
c) a DNA gene chip
d) special viral polymerase with high fidelity
d) special viral polymerase with high fidelity
To study an organism’s transcriptome by microarray, _____________ is hybridized onto DNA silica chips containing gene sequences that are ___________ to the sequence.
a) mRNA / identical
b) cDNA / identical
c) mRNA / complementary
d) cDNA / complementary
cDNA / complementary
Which is NOT a use for metagenomics?
a) studying possible connections between specific microbial populations in humans and specific diseases
b) assembling complete genomes from isolated community DNA
c) measuring gene expression in populations in order to elucidate function of a gene
d) analyzing environments for the presence and distribution of specific microbial groups
c) measuring gene expression in populations in order to elucidate function of a gene
Which is NOT true about the metabolome and metabolomics?
a) The metabolome is the complete set of an organism’s metabolic intermediates.
b) metabolomics was used to reveal the total protein complement of a particular microorganism
c) Metabolomics has been used to characterize the human skin microbiome.
d) The metabolome shows the enzymatic pathways of an organism.
b) metabolomics was used to reveal the total protein complement of a particular microorganism
Which of the following organisms is not part of the human mycobiome?
a) Clostridium
b) Saccharomyces
c) Candida
d) Cladosporium
a) Clostridium
Computers are used to assemble genomes by deducing the order of DNA fragments based on
a) overlaps
b) mass spectroscopy
c) sequence
d) well position
a) overlaps
True or False: To date, humans have been identified as having the largest genome size
a) True
b) False
False
Which type of analysis is typically used for proteomics?a) RNA-Seq
b) mass spectrometry
c) microarrays
d) PCR
b) mass spectrometry
To study an organism’s transcriptome by microarray, ______________ is hybridized onto DNA silica chips containing gene sequences that are _____to the sequence.
a) mRNA / complementary
b) mRNA / identical
c) cDNA / identical
d) cDNA / complementary
d) cDNA / complementary
Why can bacteria undergo rapid evolutionary change?
a) Bacteria pass through numerous bottlenecks
b) Bacteria experience intense selective pressure
c) Bacterial populations are large and can reproduce quickly
d) Bacteria mutate at high rates
c) Bacterial populations are large and can reproduce quickly
Which bacterial trait is NOT useful for experiments in evolution?
a) Selective pressure on bacteria is easily manipulated
b) Some bacteria are naturally transformable
c) Bacterial populations are large and reproduce quickly
d) The ancestral organism can be frozen and compared to the evolved descendant
b) Some bacteria are naturally transformable
_____________ occur(s) at greater frequency than ______________ in microbial genomes.
a) Deletions / insertions
b) Recombination / mutations
c) Insertions / deletions
d) Mutations / repairs
a) Deletions / insertions
The E. coli long-term evolution (LTEE) experiment tracked E. coli for more than _______________ generations.
a) 1,000,000
b) 10,000
c) 1,000
d) 50,000
d) 50,000
Two tubes are inoculated from the same tube containing a bacterial culture. The cultures are then transferred every day for two months. All of the media and growth conditions are the same in every tube. After two months of cultivation, the fitness and genotype frequencies of the populations in the two tubes are compared. The fitness of the two cultures is the same, but the genotype frequencies are very different in the two cultures. How is this possible?a) Genetic drift within the small populations in the test tubes resulted in different genotype frequencies
b) Natural selection caused the evolution of different genotype frequencies within the separate test tubes.
c) This result is not possible because different genotype frequencies would result in different fitness levels under the same growth conditions
d) Two months is not long enough for different fitness levels to evolve even if the genotype frequencies change
Genetic drift within the small populations in the test tubes resulted in different genotype frequencies
Both deletions and insertions occur during the evolution of microbial genomes. Insertions bring in new genes that may be useful for the cell. Deletions
a) always result in a severe loss of fitness but keep microbial genomes compact
b) may increase fitness of a microorganism by eliminating unneeded genes
c) are uncommon because they are usually lethal
d) always result in a severe loss of fitness for the microorganism
b) may increase fitness of a microorganism by eliminating unneeded genes
Chromosomal islands contain clusters of genes for
a) antibiotic resistance
b) DNA repair and replication
c) virulence, biodegradation of pollutants, and symbiotic relationships
d) catabolic and anabolic reactions
c) virulence, biodegradation of pollutants, and symbiotic relationships
It is generally accepted that independent mutation, rather than gene duplication, is the mechanism for evolution of most new genes
a) True
b) False
False
Which of the following is/are NOT produced using lactic acid bacteria?
a) antibiotics
b) buttermilk
c) silage
d) plasma extender
a) antibiotics
Proteobacteria are ALL Gram positive
a) True
b) False
False
Select the proper order
a)Domain/Phylum/Class/Order/Family/Genus/Species
b)Species/Genus/Family/Order/Class/Phylum/Domain
c)Domain/Phylum/Family/Class/Order/Genus/Species
d)Phylum/Domain/Order/Class/Family/Genus/Species
a)Domain/Phylum/Class/Order/Family/Genus/Species
Rickettsia are
a) Tenericutes
b) Firmicutes
c) Gammaproteobacteria
d) Alphproteobacteria
d) Alphproteobacteria
Genera which are characterized by 2,3-butanediol fermentation include
a) Pseudomonas, Vibro
b) Mycoplasma
c) Escherichia, Salmonella
d) Enterobacter, Klebsiella, Serratia
d) Enterobacter, Klebsiella, Serratia
Aerobic respiration and anaerobic respiration use different ________________, while chemolithotrophs and chemoorganotrophs use different _________________.
a) electron acceptors / electron donors
b) electron donors / electron acceptors
c) types of phosphorylation / carbon sources
d) proton motive force / photophosphorylation
a) electron acceptors / electron donors
The foul-smelling putrescine byproduct suggests activity of
a) amino acid fermentation by clostridia.
b) secondary fermentation.
c) sulfur-oxidizing bacteria.
d) syntrophic carbohydrate metabolism
a) amino acid fermentation by clostridia
Most mesophilic organisms can grow in a temperature range of
a) 50-65°C.
b) 20-45°C.
c) 10-20°C.
d) 0-15°C
b) 20-45°C
A halotolerant facultative anaerobe would grow BEST in which of the following environments?
a) Oxygenated non-saline
b) Oxygenated saline
c) Oxygen depleted saline
d) Oxygen depleted non-saline
a) Oxygenated non-saline
Selective medium differs from differential medium because
a) selective medium permits growth of a particular microbial type while differential medium is used to distinguish between types of organisms.
b) differential medium differentiates pathogens from nonpathogens while selective medium grows only pathogens.
c) differential medium contains growth inhibitors while selective medium does not.
d) selective medium permits growth of more organisms than differential medium
selective medium permits growth of a particular microbial type while differential medium is used to distinguish between types of organisms.
Organisms able to live in environments with high sugar concentrations are
a) anaerobic fermenting bacteria.
b) xerophiles.
c) halotolerant.
d) osmophiles
d) osmophiles
What temperature is most commonly used in autoclaves to sterilize growth media and other devices prior to experimentation?
a) 101°C
b) 121°C
c) 95°C
d) 140°C
b) 121°C
Which term is most relevant in describing the efficacy of an antimicrobial for use in a clinical setting?
a) Sterilization coefficient
b) Lethal dosage
c) Effective dose
d) Minimum inhibitory concentration (MIC)
d) Minimum inhibitory concentration (MIC)
Which method would be LEAST effective at sterilizing a glass hockey stick to use in the spread-plate method?
a) Ethanol soaking
b) Gamma radiation
c) Hight temperature short time pasteurization
d) Autoclaving
c) High temperature short time pasteurization
Alternative autotrophic routes to the Calvin cycle, such as the reverse citric acid cycle and the hydroxypropionate pathway, are unified in their requirement for
a) NAD(P)H.
b) CO2.
c) organic compound(s) formed.
d) coenzyme A
b) CO2.
Identifying carboxysomes in a bacterium suggests it
a) will use the Calvin cycle to convert the concentrated CO2 into biomass.
b) has a deficient Calvin cycle and accumulated CO2.
c) is in a carboxylic acid rich environment and is storing excess quantities for potentially harsh conditions.
d) contains the reverse citric acid cycle
a) will use the Calvin cycle to convert the concentrated CO2 into biomass.
Whether an organism is classified as a photoheterotroph or a photoautotroph depends on its
a) carbon source.
b) energy source.
c) oxygen requirements.
d) carbon and energy sources
a) carbon source
Which of the following statements is FALSE?
a) Bacteria typically divide by binary fission, producing two daughter cells.
b) In the lag phase, cell death exceeds cell division.
c) In the death phase, bacterial growth may cease as a result of oxygen and nutrient depletion.
d) The generation time of bacteria may vary from species to species
b) In the lag phase, cell death exceeds cell division.
The time between inoculation and the beginning of growth is usually called the
a) dormant phase.
b) log phase.
c) decline phase.
d) lag phase
d) lag phase
Well-designed microbial activity measurements can reveal ________ of major metabolic reactions in a habitat
a) types
b) both types and rates
c) rates
d) either types or rates (but not both)
b) both types and rates
Winogradsky columns are used primarily for enrichment of
a) aerobes, anaerobes, and phototrophs.
b) phototrophs, although occasionally heterotrophs do appear.
c) aerobic cultures, although occasionally anaerobes do appear
d) anaerobic cultures, although occasionally aerobes do appear
a) aerobes, anaerobes, and phototrophs
Turbidity measurements are commonly utilized for monitoring
a) conies.
b) planktonic cultures.
c) sessile cultures.
d) biofilms
b) planktonic cultures.
Which is one major difference between anaerobic and aerobic respiration?
a) Use of electron transport
b) Electron acceptor
c) Use of proton motive force
d) Electron donor
b) Electron acceptor
The use of chemical agents directly on exposed body surfaces to destroy or inhibit vegetative pathogens is
a) sanitization.
b) antisepsis.
c) disinfection.
d) sterilization
b) antisepsis
During fermentation, ______________ compounds both donate and accept electrons, with no need for external electron acceptors, but during respiration, ____________ electron donors are oxidized with exogenous compounds serving as electron acceptors.
a) organic / inorganic
b) inorganic / organic
c) organic / inorganic or organic
d) inorganic or organic / organic
organic / inorganic or organic