Bailey And Scotts Diagnostic Microbiology 13th Edition By Patricia M. Test Bank

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Bailey And Scotts Diagnostic Microbiology 13th Edition By Patricia M. Test Bank

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WITH ANSWERS

Bailey And Scotts Diagnostic Microbiology 13th Edition By Patricia M. Test Bank

Chapter 02: Bacterial Genetics, Metabolism, and Structure

Test Bank

 

MULTIPLE CHOICE

 

  1. Pieces of deoxyribonucleic acid (DNA) that move from one genetic element to another and contain genes for movement and genes for other features are called:
a. transposons.
b. insertion sequences.
c. plasmids.
d. chromatoids.

 

 

ANS:  A

Insertion sequences only code for movement.

 

REF:   7                    OBJ:   Level: Knowledge

 

  1. Miniature chromosomes composed of several genes in double-stranded, closed, circular structures are called:
a. transposons.
b. insertion sequences.
c. plasmids.
d. chromatoids.

 

 

ANS:  C

Plasmids can be separate entities, but transposable elements (transposons and insertion sequences) cannot.

 

REF:   5 | 7                OBJ:   Level: Knowledge

 

  1. A DNA sequence that encodes for a specific product (ribonucleic acid [RNA] or protein) is defined as a:
a. gene.
b. genome.
c. nucleotide.
d. deoxyribonucleic acid.

 

 

ANS:  A

The genome is the collection of all the genes of an organism. Nucleotides and DNA are building blocks of genes.

 

REF:   5                    OBJ:   Level: Knowledge

 

  1. The enzyme that adds nucleotide bases to each growing daughter strand in the replication process is called:
a. replication enzymes.
b. DNA polymerase.
c. insertion sequence enzymes.
d. transcriptase.

 

 

ANS:  B

DNA polymerase is a specific type of replication enzyme.

 

REF:   78                OBJ:   Level: Knowledge

 

  1. If a bacterial cell encounters unfavorable environmental conditions, then its metabolism will begin to slow until it eventually transforms into an inactive, dormant state. This survival mechanism is known as:
a. polymerization.
b. oxidation.
c. respiration.
d. sporulation.

 

 

ANS:  D

Organisms sporulate when unfavorable conditions are encountered and remain in this state until favorable conditions return.

 

REF:   21                  OBJ:   Level: Knowledge

 

  1. Teichoic acids, mycolic acids, peptidoglycan, and disaccharide-pentapeptide subunits are all building blocks of which bacterial structure?
a. Outer cell membrane
b. Flagella
c. Inner cell membrane
d. Cell wall

 

 

ANS:  D

These elements are all part of the cell walls of some types of bacteria.

 

REF:   1920            OBJ:   Level: Knowledge

 

  1. The major difference between gram-positive and gram-negative bacteria is that:
a. the peptidoglycan layer in gram-positive bacteria is substantially thinner than in gram-negative bacteria.
b. gram-positive bacteria contain a periplasmic space, whereas gram-negative bacteria do not.
c. flagella are only present in gram-positive bacteria.
d. gram-negative bacteria contain an outer membrane that functions as the cells initial barrier to the environment.

 

 

ANS:  D

Gram-negative bacteria contain an outer membrane, but gram-positive bacteria do not.

 

REF:   19                  OBJ:   Level: Knowledge

 

  1. In gene regulation and control, repression is defined as the:
a. internal change in the original nucleotide sequence of a gene or genes within an organisms genome.
b. mechanism of genetic control in which genes are induced only when the substrate to be degraded by enzymatic action is present.
c. change of the bacterial genotypes through the exchange of DNA from one cell to another.
d. mechanism of genetic control in which genes are not transcribed and therefore are not expressed in the presence of those target products in sufficient supply.

 

 

ANS:  D

To avoid waste and overproduction of enzymes in the cell, some genes are turned off by the presence of the product of that gene expression.

 

REF:   11                  OBJ:   Level: Knowledge

 

  1. In gene regulation and control, induction can be defined as the:
a. mechanism of genetic control in which genes are induced only when the substrate to be degraded by enzymatic action is present.
b. uptake of free DNA from the environment and recombination with the recipients homologous DNA.
c. mechanism of genetic control in which genes are not transcribed and therefore are not expressed in the presence of those target products in sufficient supply.
d. change of the bacterial genotypes through the exchange of DNA from one cell to another.

 

 

ANS:  A

To avoid waste and overproduction of enzymes in the cell, some genes are turned on only by the presence of the substrate of that gene expression.

 

REF:   11                  OBJ:   Level: Knowledge

 

  1. Mutation is defined as the:
a. change of the bacterial genotypes through the exchange of DNA from one cell to another.
b. internal change in the original nucleotide sequence of a gene or genes within an organisms genome.
c. process by which genetic elements such as plasmids and transposons excise from one genomic location and insert into another.
d. uptake of free DNA from the environment and recombination with the recipients homologous DNA.

 

 

ANS:  B

Mutation occurs as an internal change in the original nucleotide sequence of a gene or genes within an organisms genome.

 

REF:   12                  OBJ:   Level: Knowledge

 

  1. Recombination is defined as the:
a. change of the bacterial genotypes through the exchange of DNA from one cell to another.
b. internal change in the original nucleotide sequence of a gene or genes within an organisms genome.
c. process by which genetic elements such as plasmids and transposons excise from one genomic location and insert into another.
d. uptake of free DNA from the environment and recombination with the recipients homologous DNA.

 

 

ANS:  A

Recombination is an event that frequently occurs in many varieties of bacteria and is a major means by which bacteria may achieve genetic diversity.

 

REF:   12                  OBJ:   Level: Knowledge

 

  1. Transformation is defined as the:
a. change of the bacterial genotypes through the exchange of DNA from one cell to another.
b. internal change in the original nucleotide sequence of a gene or genes within an organisms genome.
c. process by which genetic elements such as plasmids and transposons excise from one genomic location and insert into another.
d. uptake of free DNA from the environment and recombination with the recipients homologous DNA.

 

 

ANS:  D

Transformation involves recipient uptake of DNA that is free in the environment when another bacterial cell dies and undergoes lysis.

 

REF:   12                  OBJ:   Level: Knowledge

 

  1. Transduction is defined as the:
a. change of the bacterial genotypes through the exchange of DNA from one cell to another.
b. internal change in the original nucleotide sequence of a gene or genes within an organisms genome.
c. process by which genetic elements such as plasmids and transposons excise from one genomic location and insert into another.
d. mechanism that is mediated by viruses, by which DNA from two bacteria may come together in one cell, thus allowing for recombination.

 

 

ANS:  D

Bacteriophages, viruses that infect bacteria, integrate their DNA into the bacterial cells chromosome, in which viral DNA replication and expression is directed; thus, the DNA is dispersed to another bacterium when other cells are infected.

 

REF:   12                  OBJ:   Level: Knowledge

 

  1. The mechanism for adenosine triphosphate (ATP) production in which high-energy phosphate bonds produced by the central metabolic pathways are donated to adenosine diphosphate (ADP) to form ATP is:
a. substrate-level phosphorylation.
b. fermentative metabolism.
c. oxidative phosphorylation.
d. aerobic respiration.

 

 

ANS:  A

Fermentative metabolism is one form of substrate-level phosphorylation that does not require oxygen. Oxidative phosphorylation is an electron transport system that can use either oxygen as the terminal electron acceptor (aerobic respiration) or acceptors other than oxygen (anaerobic respiration).

 

REF:   15                  OBJ:   Level: Knowledge

 

  1. A pathway that generates ATP by substrate-level phosphorylation that does not require oxygen and produces various end products, including alcohols, acids, carbon dioxide, and hydrogen, is:
a. substrate-level phosphorylation.
b. fermentative metabolism.
c. oxidative phosphorylation.
d. aerobic respiration.

 

 

ANS:  B

Fermentative metabolism is one form of substrate-level phosphorylation that does not require oxygen. Oxidative phosphorylation, including both aerobic respiration and anaerobic respiration, is an electron transport system.

 

REF:   15                  OBJ:   Level: Knowledge

 

  1. The pathway of metabolism that involves a series of electron transfers from reduced carrier molecules such as NADH2 and NADPH2 to a terminal electron acceptor is:
a. substrate-level phosphorylation.
b. fermentative metabolism.
c. oxidative phosphorylation.
d. aerobic respiration.

 

 

ANS:  C

Fermentative metabolism is one form of substrate-level phosphorylation. Oxidative phosphorylation is an electron transport system that can use either oxygen as the terminal electron acceptor (aerobic respiration) or acceptors other than oxygen (anaerobic respiration).

 

REF:   17                  OBJ:   Level: Knowledge

 

  1. The term used when oxidative phosphorylation uses oxygen as the terminal electron acceptor is:
a. substrate-level phosphorylation.
b. fermentative metabolism.
c. anaerobic respiration.
d. aerobic respiration.

 

 

ANS:  D

Oxidative phosphorylation is an electron transport system that can use either oxygen as the terminal electron acceptor (aerobic respiration) or acceptors other than oxygen (anaerobic respiration).

 

REF:   17                  OBJ:   Level: Knowledge

 

  1. Which organelle is found in eukaryotic cells and is responsible for controlled enzymatic degradation of intracellular substances?
a. Mitochondria
b. Lysosomes
c. Endoplasmic reticulum
d. Golgi body

 

 

ANS:  B

Lysosomes in the cell are responsible for controlled degradation of intracellular substances.

 

REF:   18                  OBJ:   Level: Knowledge

 

  1. Teichoic acids are:
a. waxy substances that are found in some bacterial cell walls that make the cells resistant to toxic substances, including acids.
b. glycerol- or ribitol-phosphate polymers that are combined with various sugars, amino acids, and amino sugars, which are a part of the cell wall of gram-positive bacteria.
c. highmolecular-weight polysaccharides that coat some bacterial cells and protect the bacteria from attack by cells of the human defense system.
d. hairlike, proteinaceous structures that extend from the cell.

 

 

ANS:  B

Teichoic acids, mycolic acids, peptidoglycan, and disaccharide-pentapeptide subunits are all building blocks of the bacterial cell wall.

 

REF:   19                  OBJ:   Level: Knowledge

 

  1. Pieces of DNA that move from plasmid to chromosome or vice versa but are not found as separate entities are called:
a. DNA polymerases.
b. transposable elements.
c. plasmids.
d. chromatoids.

 

 

ANS:  B

Plasmids can be separate entities, but transposable elements cannot.

 

REF:   7                    OBJ:   Level: Knowledge

 

  1. All genes within an organism make up that organisms:
a. chromosomes.
b. genome.
c. nucleotides.
d. DNA.

 

 

ANS:  B

Chromosomes are elements of the genome. Nucleotides and DNA are building blocks of genes.

 

REF:   5                    OBJ:   Level: Knowledge

 

  1. A bacterial cell that contains teichoic acid stains which color on the Gram stain?
a. Pink
b. Red
c. Green
d. Purple

 

 

ANS:  D

Gram-positive organisms contain teichoic acid and therefore stain purple on the Gram stain.

 

REF:   18                  OBJ:   Level: Application

 

  1. A bacterial cell that contains an outer membrane and periplasmic space stains pink to red on Gram stain. Which one of the following statements explains this discrepancy?
a. The bacteria were subjected to too much alcohol during the decolorization process, causing the organism to absorb the pink-to-red dye.
b. The bacteria with an outer membrane and periplasmic space should not be Gram stained because of their cell wall content.
c. Something is wrong with the lot of stains and may be expired.

The gram stain reagents are most likely expired.

d. No discrepancy is present; organisms that contain an outer membrane and periplasmic space should stain pink because of their cell wall composition.

 

 

ANS:  D

Gram-negative organisms contain an outer membrane and periplasmic space and therefore should stain red to pink to red on Gram stain because of their cell wall composition.

 

REF:   18                  OBJ:   Level: Problem Solving

 

  1. Amino acids, fatty acids, sugars, and nucleotides are produced during which metabolic reaction?
a. Fueling
b. Biosynthesis
c. Polymerization
d. Assembly

 

 

ANS:  B

During biosynthesis, amino acids, fatty acids, sugars, and nucleotides are produced using precursor products in dozens of pathways to produce nearly 100 different products.

 

REF:   18                  OBJ:   Level: Knowledge

 

  1. Which of the following processes takes place in the cytoplasm and involves the transfer RNA (tRNA) mediating the sequential addition of amino acids in a specific sequence that is dictated by the codon sequence of the messenger RNA (mRNA) molecule?
a. Transcription
b. Initiation
c. Elongation
d. Termination

 

 

ANS:  C

Elongation, which is one of the steps of translation, adds amino acids in a specific sequence, which ultimately codes for a specific protein. Translation occurs in the cytoplasm, whereas transcription occurs in the nucleus. Initiation begins with the association of ribosomal subunits, mRNA, and formylmethionine tRNA carrying the initial amino acid of the protein to be synthesized. After the initial complex is formed, addition of individual amino acids begins. Termination is the final step in translation and occurs when the ribosomal A site encounters a stop codon that does not specify an amino acid.

 

REF:   9                    OBJ:   Level: Knowledge

 

 

Chapter 04: Laboratory Safety

Test Bank

 

MULTIPLE CHOICE

 

  1. Air flow in a microbiology laboratory should be:
a. from lower to higher risk areas.
b. minimized as much as possible.
c. optimized to prevent the settling of dangerous aerosols.
d. well-filtered by recirculating it through numerous filters before recycling.

 

 

ANS:  A

The air-handling system of a microbiology laboratory should move air from a lower to a higher risk area, never the reverse.

 

REF:   46                  OBJ:   Level: Knowledge

 

  1. The agency that requires health care facilities to provide employees with all devices and mechanisms necessary to protect them from the hazards encountered in the laboratory is:
a. Department of Health and Environmental Control (DHEC).
b. Occupational Safety and Health Administration (OSHA).
c. Centers for Disease Control and Prevention (CDC).
d. Health Emergency Planning Advisor (HEPA).

 

 

ANS:  B

Many government agencies have been developed to help protect the public from harm involving infectious agents and other laboratory safety hazards. OSHA is one of them.

 

REF:   41                  OBJ:   Level: Knowledge

 

  1. Procedures such as grinding, mincing, vortexing, and preparing smears:
a. are hazardous and should be performed while wearing gloves and gown protection.
b. create aerosol droplets and should be performed only in an approved biosafety cabinet.
c. should be avoided with specimens known to contain infectious agents.
d. produce a spill hazard and should be performed over an absorptive mat.

 

 

ANS:  B

All of these procedures create hazards by dispersing infectious material into the air and should be confined to protective equipment such as a safety cabinet.

 

REF:   46                  OBJ:   Level: Knowledge

 

  1. Class I biological safety cabinets:
a. sterilize the air as it passes over the material in the cabinet.
b. protect the environment from contamination by biological agents by filtering the air as it is exhausted from the cabinet.
c. are completely enclosed and have gloves that enable the worker to manipulate the material in the cabinet.
d. are often called laminar flow hoods.

 

 

ANS:  B

Biological safety cabinets are designated by class according to the degree of biological containment they provide, from the lowest level of containment (class I) to the highest level of containment (class III).

 

REF:   47                  OBJ:   Level: Knowledge

 

  1. Optimal protection of specimen, personnel, and environment is accomplished with which class of biological safety cabinet?
a. Class I
b. Class II
c. Class III
d. Class IV

 

 

ANS:  C

Biological safety cabinets are designated by class according to the degree of biological containment they provide, from the lowest level of containment (class I) to the highest level of containment (class III).

 

REF:   47                  OBJ:   Level: Knowledge

 

  1. The method of choice for sterilizing items such as antibiotic solutions, chemicals, radioisotopes, and vaccines that are heat-sensitive is:
a. dry, low temperature heat.
b. moist, low temperature heat.
c. filtration.
d. chemical.

 

 

ANS:  C

A filtration method that does not use heat is the method of choice for sterilizing items that are heat sensitive.

 

REF:   40                  OBJ:   Level: Knowledge

 

  1. To be sterilized in an autoclave, infectious medical waste should be:
a. packed tightly to avoid dangerous pressure pockets.
b. processed for 15 to 20 minutes at 121 C and 30 pounds per square inch (psi) pressure.
c. processed for 30 to 60 minutes at 132 C and 15 psi pressure.
d. processed for at least 1 hour at 121 C and 15 psi pressure.

 

 

ANS:  C

Proper temperature, pressure, and exposure time varies, depending on the type of material being sterilized. Highly contaminated items such as infectious waste are more vigorously treated than items such as media or instruments.

 

REF:   40                  OBJ:   Level: Knowledge

 

  1. The autoclave sterilizes material by:
a. applying dry heat at high temperatures and pressure.
b. infusing gaseous chemicals that kill organisms.
c. applying moist heat at high temperatures and increased pressure.
d. cleaving protein bonds found in most biological agent cell walls.

 

 

ANS:  C

Several ways are used to sterilize material in the laboratory. Moist heat at high temperature and pressure (autoclave), dry heat (ovens), pulling solution through a membrane with a vacuum (filtration), radiation, and chemicals are all used, depending on the material involved.

 

REF:   3940            OBJ:   Level: Knowledge

 

  1. The most effective antiseptic agent against blood spills and therefore the antiseptic of choice in laboratories where these agents are likely found is:
a. 70% ethanol.
b. phenol compound.
c. absolute ethanol.
d. 10% bleach.

 

 

ANS:  D

Bleach is an effective antiseptic agent against hepatitis B virus (HBV), human immunodeficiency virus (HIV), and blood spills and is the antiseptic of choice in many laboratories.

 

REF:   41                  OBJ:   Level: Knowledge

 

  1. Standard precautions in the microbiology laboratory apply to:
a. all clinical specimens.
b. clinical specimens that contain blood or body fluids.
c. blood, body fluids, feces, sputum, saliva, urine, and vomitus.
d. only specimens that are visibly bloody.

 

 

ANS:  B

Not all specimens carry the hazard of blood-borne pathogens; therefore not all specimens must be treated as strictly as those that contain blood or bodily fluids.

 

REF:   4546            OBJ:   Level: Knowledge

 

  1. Standard precautions include:
a. using barrier devices to prevent exposure to skin and mucous membranes.
b. recapping needles by hand.
c. storing drinks but not food in laboratory refrigerators.
d. discarding sharps in plastic biohazard bags.

 

 

ANS:  A

Using barrier devices to prevent exposure to skin and mucous membranes is an essential standard laboratory precaution that should be adhered to by all laboratory personnel.

 

REF:   45                  OBJ:   Level: Knowledge

 

  1. Mouth pipetting:
a. should be performed only if necessary and with extreme care.
b. can save valuable time and should be performed whenever quick results are needed.
c. is performed only when material is not expected to pose a biological hazard.
d. should not be performed in any circumstance in the clinical laboratory.

 

 

ANS:  D

Mouth pipetting is a dangerous practice that should never be performed in the clinical laboratory.

 

REF:   46                  OBJ:   Level: Knowledge

 

  1. Biosafety Level 1 agents:
a. include those that are the common agents of an infectious disease.
b. require only standard good laboratory techniques.
c. include Mycobacterium tuberculosis, M. gordonae, and Brucella.
d. require the use of maximum containment facilities.

 

 

ANS:  B

Biological agents are classified into levels based on their degree of potential harm, from nonhazardous (Level 1) to the most hazardous (Level 4).

 

REF:   49                  OBJ:   Level: Knowledge

 

  1. Working with biosafety Level 3 agents requires:
a. U.S. Department of Agriculture (USDA) credentials and a postgraduate degree in microbiology or a related field.
b. laboratory design features that control air movement.
c. personnel to wear protective clothing and devices and enter a decontaminating chamber before leaving.
d. workers to have blood samples routinely tested to rule out infection or contamination.

 

 

ANS:  B

Biological agents are classified into levels, based on their degree of potential harm, from nonhazardous (Level 1) to the most hazardous (Level 4).

 

REF:   49                  OBJ:   Level: Knowledge

 

  1. A cleaning solution used on the laboratory bench top to kill bacteria that are potentially harmful to humans would be called a(n):
a. surfactant.
b. disinfectant.
c. biocide.
d. antiseptic.

 

 

ANS:  B

A disinfectant is used on inanimate objects to kill bacteria that are potentially harmful to humans, whereas an antiseptic is a disinfectant that is generally used on living tissue such as skin.

 

REF:   41                  OBJ:   Level: Application

 

  1. A cleaning solution used on the venipuncture site to avoid skin contamination of the blood sample is called a(n):
a. surfactant.
b. disinfectant.
c. biocide.
d. antiseptic.

 

 

ANS:  D

A disinfectant is used on inanimate objects to kill bacteria that are potentially harmful to humans, whereas an antiseptic is a disinfectant that is generally used on living tissue such as skin.

 

REF:   41                  OBJ:   Level: Application

 

  1. Information concerning a chemical products health hazards, toxicity, and disposal procedures is:
a. found in the manufacturers material safety data sheets (MSDS).
b. found on the product label.
c. proprietary information and only released at the manufacturers discretion.
d. obtained through the manufacturers technical support division; acquiring access to that information is the responsibility of the laboratory worker.

 

 

ANS:  A

The MSDS are supplied by manufacturers to notify laboratory personnel of the potential dangers of the product in question and should be kept on hand and available at all times.

 

REF:   4142            OBJ:   Level: Knowledge

 

  1. The agency that has published a guide to hazardous waste reduction is:
a. DHEC.
b. OSHA.
c. CDC.
d. U.S. Environmental Protection Agency (EPA).

 

 

ANS:  D

Many government agencies have been developed to help protect the public from harm involving infectious agents and other safety hazards. The EPA is one such agency.

 

REF:   44                  OBJ:   Level: Knowledge

 

  1. The agency that has published guidelines known as standard precautions to reduce the risk of disease transmission in laboratories is:
a. DHEC.
b. OSHA.
c. CDC.
d. EPA.

 

 

ANS:  C

Many government agencies have been developed to help protect the public from harm involving infectious agents and other safety hazards. The CDC is one such agency.

 

REF:   45                  OBJ:   Level: Knowledge

 

  1. The agency that has published guidelines regarding the packaging of biohazardous specimens is known as:
a. DHEC.
b. International Air Transport Association (IATA).
c. CDC.
d. EPA.

 

 

ANS:  B

Many government agencies have been developed to help protect the public from harm involving infectious agents and other safety hazards. The IATA is one such agency.

 

REF:   50                  OBJ:   Level: Knowledge

 

  1. Class III biological safety cabinets:
a. sterilize the air as it passes over the material in the cabinet.
b. protect the environment from contamination by biological agents by filtering the air as it is exhausted from the cabinet.
c. are completely enclosed and have gloves that enable the worker to manipulate the material in the cabinet.
d. are often called laminar flow hoods.

 

 

ANS:  C

Biological safety cabinets are designated by class according to the degree of biological containment they provide, from the lowest level of containment (class I) to the highest level of containment (class III).

 

REF:   4748            OBJ:   Level: Knowledge

 

  1. Minimal protection of specimen, personnel, and environment is accomplished with which class of biological safety cabinet?
a. Class I
b. Class II
c. Class III
d. Class IV

 

 

ANS:  A

Biological safety cabinets are designated by class according to the degree of biological containment they provide, from the lowest level of containment (class I) to the highest level of containment (class III).

 

REF:   47                  OBJ:   Level: Knowledge

 

  1. To be sterilized in an autoclave, media or instruments should be:
a. packed tightly to avoid dangerous pressure pockets.
b. processed for 15 minutes at 121 C and 15 psi pressure.
c. processed for 30 to 60 minutes at 132 C and 15 psi pressure.
d. processed for at least 1 hour at 121 C and 15 psi pressure.

 

 

ANS:  B

Proper temperature, pressure, and exposure time varies, depending on the type of material being sterilized. Highly contaminated items such as infectious waste are more vigorously treated than items such as media or instruments.

 

REF:   40                  OBJ:   Level: Knowledge

 

  1. Biosafety Level 2 agents:
a. include those that are the common agents of infectious disease.
b. require only standard good laboratory technique.
c. include Mycobacterium tuberculosis, M. gordonae, and Brucella.
d. require the use of maximum containment facilities.

 

 

ANS:  A

Biological agents are classified into levels on the basis of their degree of potential harm, from nonhazardous (Level 1) to the most hazardous (Level 4).

 

REF:   49                  OBJ:   Level: Knowledge

 

  1. Biosafety Level 4 agents:
a. include those that are the common agents of infectious disease.
b. require only standard good laboratory technique.
c. include Mycobacterium tuberculosis, M. gordonae, and Brucella.
d. require the use of maximum containment facilities.

 

 

ANS:  D

Biological agents are classified into levels on the basis of their degree of potential harm, from nonhazardous (Level 1) to the most hazardous (Level 4).

 

REF:   50                  OBJ:   Level: Knowledge

 

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