Which of the following leukocyte functions do macrophages carry out?
A) phagocytosis of pathogens and production of NETs
B) phagocytosis of pathogens and debris
C) secretion of leukotrienes
D) phagocytosis of pathogens and secretion of alpha interferons and leukotrienes
E) release of alpha interferon
D
Antiviral medications can best be described as
A) antibiotics produced by bacteria
B) synthetic antimicrobials
C) extremely narrow spectrum synthetic antimicrobials
D) broad spectrum antimicrobials
E) extremely narrow spectrum antimicrobials
C
Which of the following is/are common to chemiosmosis and the light-dependent reactions of photosynthesis?
A) reduction of NADP+ only
B) electron transport only
C) a proton gradient only
D) both electron transport and proton gradient
E) electron transport, a proton gradient, and reduction of NADP+
D
Which condition occurs when antibodies bind to and stimulate receptors that elicit production of thyroid hormone and growth of the thyroid gland?
A) DiGeorge syndrome
B) farmer's lung
C) multiple sclerosis
D) type 1 diabetes
E) Graves' disease
E
Phagocytes directly detect microbial molecules like LPS and peptidoglycan by means of
A) compliment cascade
B) cell- like receptors
C) PAMPs
D) interferon receptors
E) bradykinin binding
B
The incidence of tuberculosis in the year 2000 in the United States was 12.43/100,000 cases. This means
A) 12.43 of every 100,000 people died of tuberculosis in the U.S. in the year 2000.
B) 12.43 of every 100,000 cases of tuberculosis were treated in the United States in the year 2000
C) 12.43 in every 100,000 people in the United States had tuberculosis in the year 2000
D) there were 12.43 tubercle bacilli per 100,000 microbes in the United States in the year 2000
E) there were 12.43 new cases of tuberculosis for every 100,000 people in the United States in the year 2000
E
If you started with a single DNA molecule, how many would you have at the end of six PCR?
A) 6
B) 16
C) 32
D) 64
E) 100
D
The condition called parasitism is characterized as a(n)
A) relationship between two organisms where both members benefit
B) relationship between two organisms where one member harms the other
C) unsuccessful microbial invasion due to the presence of preexisting microbes
D) nonsymbiotic relationship
E) relationship between two organisms where only one member benefits and the other is unharmed
B
The bacterial chromosome is
A) usually circular
B) found in nucleoid
C) found in a nucleus
D) both circular and found in a nucleoid
E) both circular and found in a nucleus
C
Fever is beneficial during viral infection because the higher temperature
A) results in virus being shred in sweat
B) prevents viral infection of fibrobalsts
C) denatures viral protein
D) increases the effectiveness of interferons
E) increases vasodilation, bringing more leukocytes to the site of infection
E
Which of the following statements about the endoplasmic reticulum (ER) id CORRECT?
A) The ER is a lipid storage organelle
B) The smooth ER has ribosomes associated with it
C) The rough ER is the site of lipid synthesis
D) The ER is a transport system within the cytoplasm
E) The smooth ER is a site of ATP synthesis
D
Which of the following statements is CORRECT about bacterial transcription?
A) Rho protein is required for termination of transcription
B) The mRNA is extensively modified before transcription
C) A single RNA polymerase produces all RNA transcripts
D) Various sigma factors recognize different promoter sequences
E) It occurs in the periplasm
D
Which of the following statements regarding virus taxonomy is TRUE?
A) The species epithet statements is a Latin descriptor of the virion structure.
B) Virus classes are based on the domain of the host organism
C) Some virus family names are derived from the name of an important member of the family
D) Virus classes are well established
E) Viruses are classified on the basis of the taxonomy of their host organism
C
Which of the following describes flash pasteurization?
A) heating at 134oC for one second
B) heating at 72oC for 15 seconds
C) heating at 72oC for 15 minutes
D) passing liquid through steam at 140oC
E) heating at 63oC for 30 minutes
B
Which of the following combinations of pathogen and virulence factor is CORRECT?
A) Staphylococcus aureus and neurotoxins
B) Escherichia coli and cytotoxin
C) Streptococcus pyogenes and protein M
D) Gram-positive bacteria and lipid A
E) Neisseria gonorrhea and endotoxin
C
Which of the following is found in eukaryotic cells?
A) nuclear envelope
B) ribosomes
C) DNA
D) cytoplasm
E) cytoplasmic membrane
A
Which of the following would test positive for the tuberculin response?
A) someone who has been immunized with the tuberculosis vaccine
B) someone who has previously had tuberculosis
C) someone who has previously been injected subcutaneously with tuberculin
D) someone who has been immunized with the tuberculosis vaccine or has previously had tuberculosis
E) someone who has been immunized with the tuberculosis vaccine or previously been injected subcutaneously with tuberculin
D
If a microbiology lab student left the safranin out of the Gram stain procedure, what would be the result?
A) All cells would be pink
B) Gram- positive cells would be pink and Gram- negative cells would be purple
C) Gram-positive cells would be purple and Gram-negative cells would be colorless
D) Gram- positive cells would be colorless and Gram- negative cells would be pink
E) All cells would be purple
C
Aerobic free-living Gram-negative bacilli in the phylum Proteobacteria that are capable of metabolizing a wide range of organic compounds are members of the genus
A) Cytophagia
B) Salmonella
C) Rickettsia
D) Pseudomonas
E) Vibrio
D
First line of defense may be described as
A) damage resulting in cell lysis
B) nonspecific leukocytes that secrete toxins onto the surface of virally infected cells
C) the coating of a pathogen by a complement
D) intact skin mucous membranes, sebum, tears, and so forth
E) the release of prostaglandins and leukotrienes in response to microbes
D
Which of the following statements regarding phagocyte recognition of pathogens is TRUE?
A) TLRs in the phagocyte cytoplasmic membrane bind surface structures of microbes
B) TLRs on the surface of microbes trigger the accumulation of opsonins
C) Lectins on the surface of microbes are bound by chemokine receptors
D) NOD proteins on the surface of microbes are detected by TLRs
E) MACs on the surface of microbes are detected by NOD proteins
A
During a visit to a hospital, a child receives the oral polio vaccine. He then returns to his distant village. Sometime later a polio outbreak occurs in the village, but the child and his siblings, who had not had the vaccine, are spread. What is the explanation for this event?
A) active immunity
B) natural immunity
C) passive immunity
D) herd immunity
E) contact immunity
E
A new virus is discovered that causes cells to clump together. Which of the following types of assay would be useful for diagnosing infection with the virus?
A) both agglutination and complement fixation tests
B) viral hemagglutination
C) agglutination
D) hemagglutination
E) complement fixation test
B
A(n) ___ can be used to detect cytopathic virus particles.
A) viral hemagglutination inhibition
B) direct fluorescent antibody
C) immunodiffusion precipitation
D) western blot
E) viral neutralization
E
What is the relationship between prevalence and incidence for an acute disease like influenza?
A) the incidence and prevalence are essentially equal
B) the prevalence is always greater than the incidence
C) The incidence rises while prevalence declines
D) the incidence is always greater than the prevalence
E) there is no predictable relationship
A
The CDC issued alerts about a bacterial strain known as NDM1 (New Delhi metalo- lactamase 1). What type of antibiotic resistance is indicated by the name?
A) change in the permeability of the drug
B) alteration of the target of the drug
C) overproduction of an enzyme in a key metabolic pathway
D) inactivation of the drug
E) removal of the drug via a pump
D
The bacterium that causes tuberculosis can be expelled from the lungs by a cough and remain viable in the air for an hour or more. If a person inhales the bacteria from the air, what type of transmission has occurred?
A) foodborne
B) waterborne
C) indirect contact
D) bodily fluid
E) airborne
E
Viruses are NOT included in the taxonomic scheme proposed by Carl Woese because they lack
A) ribosomal RNA
B) genetic material
C) lipid membranes
D) proteins
E) cytoplasm
A
Anti- human antibodies ( specific for human IgG antibodies) with fluorescent molecules covalently attached are used for
A) direct ELISAs
B) direct fluorescent antibody tests
C) indirect fluorescent antibody tests
D) indirect ELISAs
E) both indirect ELISAs and indirect fluorescent antibody tests
E
Severe malnutrition may lead to immunodeficiency by
A) preventing to proliferation of B cells
B) promoting the development of food allergies
C) triggering an inflammatory response
D) decreasing the ability of the body to produce phagocytes
E) triggering the proliferation of T cells
A
What is the result when a dendritic cell phagocytizes a microbe and processes it?
A) display of microbial fragments with CD8 glycoproteins
B) suppression of the immune response to the microbe
C) activation of the dendritic cell to become a plasma cell
D) display of epitope - MHC 1 complexes on the surface of the cell
E) display of microbial epitope- MHC II complexes on the cell surface
E
What are the "sticky ends" produced by some restriction enzymes?
A) sticky ends are DNA strands with an extra hydroxyl group on the end
B) sticky ends are able to hydrogen bond with complementary strands
C) sticky ends are DNA strands able to form phosphate bonds with free DNA ends
D) sticky ends are short single-stranded ends of DNA able to hydrogen bond with complementary strands
E) sticky ends are short single-strand ends of a DNA molecule
D
Which of the following statements os CORRECT about BOTH bacterial and eurkaryotic DNA replication?
A) the lagging strand is synthesized in fragments of about 1000 or so bases
B) each chromosome has multiple origins of replication
C) replication proceeds bidirectionally from the origin of replication
D) a single DNA polymerase is responsible for both leading strand and lagging strand synthesis
E) AN RNA primase is required for initiation of synthesis
C
How is the development of autoimmunity normally prevented?
A) T lymphocytes require a specific set of cytokine signals to become activated
B) clonal deletion of T cells, lack of necessary cytokine signals, and regulatory T cell suppression prevent activation of autoreactive T cells
C) T lymphocytes that respond to autoantigens in the thymus undergo clonal deletion
D) Regulatory T cells suppress autoimmune responses
E) clonal deletion of T cells and regulatory T cell suppression prevent autoreactive T cell activation
B
A sick child may have influenza or RSV. These virus infections have different treatment options, so the physician requests antibody titer tests. The results are as follows: anti-influenza antibodies are primarily IgM, and anti-RSV antibodies are all IgA and IgG. Which of the following is the most appropriate interpretation?
A) The child has a current RSV infection and was previously exposed to influenza.
B)The child has concurrent influenza and RSV infections.
C) The child currently has influenza and has previously been exposed to RSV.
D) The child has neither influenza nor RSV.
E) The results do not provide sufficient data to draw a conclusion.
C
Parasitic worms, even meters-long tapeworms, are studied in microbiology because
A) diagnosis usually involves microscopic examination of patient samples
B) they are parasites
C) the Gram stain can be used to identify them
D) no one else wants to study them
E) Leeuwenhoek first discovered them
A
Which of the following statements concerning rheumatoid arthritis (RA) is TRUE?
A) Accumulations of antibody complexes lead to inflammation in and destruction of the joints
B) It occurs in humans and animals
C) There is no genetic influence on the likelihood of developing RA
D) The symptoms are due to damage caused by cytotoxic T cells
E) The onset of a disease is clearly correlated with having been infected with a specific microbe
A
Which of the following might result in nosocomial infection (HAI)?
A) a hospital aide forgetting to wash his or her hands before tending a patient
B) being bitten by an infected insect
C) having unprotected sexual intercourse
D) using a contaminated needle
E) eating contaminated food
A
Modified corn strains that produce an insect toxins from a bacterial gene are an example of
A) transgender organism
B) transgenic organism
C) vectors
D) protoplasts
E) gene therapy
B
The protozoan that causes malaria is an intracellular parasite of red blood cells (RBCs). An adaptive immune response to this parasite is problematic because
A) RBCs normally produce cytokines necessary for adaptive immune response, which this infection prevents
B) complement cannot effectively destroy RBCs
C) The parasite damages leukocytes along with RBCs
D) RBCs never enter lymphoid tissue
E) red blood cells do not produce MHC and therefore do not display the fact that they have been infected by resenting antigen
E
The condition known as microbial antagonism may be defined as
A) a relationship between two organisms where only one member benefits
B) a relationship between two organisms where both members benefit
C) an unsuccessful microbial invasion due to the presence of preexisting microbes
D) a relationship between two organisms where one member harms the other
E) microorganisms that remain with a person throughout life
C
Which of the following is the most appropriate pairing of microbe and biosafety level?
A) Ebola, BSL-2
B) methicillin-resistant Staphylococcus aureus (MRSA), BSL-2
C) E.coli, BSL-1
D) tuberculosis ,BSL-1
E) anthrax, BSL-1
B
Host specificity of a virus is due to
A) differences in size between the virus and the host cell
B) particular genes that it shares with the infected cell
C) interactions between viral and cellular surface molecules
D) the presence or absence of a cell wall on the host cell
E) the presence of an envelope
C
Mutagens are useful in biotechnology research for
A) producing new organisms which have beneficial traits from two or more organisms
B) selecting genetic mutants resistant to radioactivity
C) Producing DNA fragments for cloning
D) removing undesirable traits from microbes
E) producing organisms with altered phenotypes
E
What feature of the skin creates physical barrier to microbial invasion?
A) the surface is constantly patrolled by phagocytic cells
B) the outer layer are dead cells, tightly linked together, and are frequently shed
C) the oil secreted onto the surface of the skin traps microbes, preventing penetration
D) the outer layers are composed of cells full of protein which for NETs to trap microbes until they are shed
E) the fine hairs move microbes to mucous membranes for phagocytosis
B
When mast cells degranulate and release histamine, which of the following events may occur?
A) increased mucous production
B) bronchial spasms
C) constriction of small blood vessels
D) both constriction of small blood vessels and bronchial spasms
E) both bronchial spasms and increased mucous production
D
You open a jar that has been in the refrigerator for a couple of weeks and find the contents do not look or smell right. What type of microbe has been growing in your refrigerator?
A) thermophile
B) thermoduric
C) psychrophile
D) hyperthermophile
E) mesophile
C
Which of the following statements is MOST accurate concerning metabolism?
A) metabolism is the assembly of small molecules into macromolecules
B) metabolism is the production and expenditure of chemical energy
C) metabolism is all the chemical reactions of the organism, both anabolic and catabolic
D) metabolism is the assembly of macromolecules into cellular structures
E) metabolism is the digestion of nutrients to release energy
C
The leukocytes called natural killer lymphocytes
A) increased in allergies and helminth infection
B) respond to the coating of a pathogen by complement
C) are specialists in killing bacteria
D) are nonspecific leukocytes that secrete toxins onto the surface of virally infected cells
E) release prostaglandins and leukotrienes in response to microbes
D
Which of the following statements concerning Koch's postulates is false?
A) all of Koch's postulates must be satisfied before an organism can be shown to cause a particular disease
B) Koch's postulate involve the experimental infection of susceptible hosts
C) a suspected pathogen must be able to be grown in the laboratory
D) Koch's postulate cannot be used to demonstrate the cause of all disease
E) the suspected pathogen may not be present in all cases of the disease being studied
E
Which of the following statements concerning reduction reactions is FALSE?
A) an electron acceptor becomes more positively charged
B) they frequently involve electron carrier molecules
C) they are coupled with oxidation reactions
D) a molecule gains a hydrogen atom
E) an electron acceptor gains an electron
A
Titration is a serological procedure that
A) must be done before the western blot test to diagnose HIV
B) identifies the causative microbe of an infectious disease
C) is used for blood grouping
D) has been replaced by genetic engineering in isolating the antigen of a pathogen
E) determine the amount of an antibody in the blood
E
The compliment fixation test uses red blood cells as the target for complement activation. Test serum containing antibodies is combined with a known amount of antigen in a tube, and then the RBCs and antibodies against the RBCs are added. A positive result for the complement fixation test would be
A) loss of color in the tube
B) a cloudy solution in the tube
C) a fluorescent precipitate
D) a line of precipitate near the bottom of the tube
E) a solution that is clear due to the precipitation or RBCs
B
A research microbiologist wants to determine whether a microbe can metabolize a new synthetic organic molecule composed of carbon, hydrogen and oxygen. Which of the following would be useful in tracing the fate of the compound?
A) the 2H isotope
B) the 12C isotope
C) the 14C isotope
D) the 13C isotope
E) the 13C+ ion
C
A new influenza strain appears and is spreading rapidly. What measure might be taken by public health agencies to stop the spread?
A) shut down public transportation
B) educate the public, promote vaccination, and treat those who are infected
C) Facilitate access to vaccines
D) educate members of the public about ways to protect themselves
E) identify and treat people who are infected
B
An antimicrobial that inhibits cell wall synthesis will result in which of the following?
A) Ribosomes lose their function
B) the sterols in the cell wall become nonfunctional
C) the replication of cells, including cancer cells, slow down
D) cells cannot attach to their hosts
E) cells become more susceptible to osmotic pressure
C
The saliva of a highly venomous reptile is found to contain multiple toxic compounds. What is a practical approach to providing people with protection from deadly effects of a bite from this reptile?
A) Use recombinant techniques to prepare modified versions of the toxins
B) prepare antibodies from the blood of people who survived bites to prepare antisera
C) prepare extracts of the toxins, inactivate them, and use them one at a time in a series of immunizations
D) prepare hybridomas specific for each toxin and use the resulting monoclonal antibodies for passive immunotherapy
E) prepare antitoxins by immunizing a large animal with the toxins, and use extracted antibodies for treating exposed persons
E
A small amount of antigen is injected under the skin of a patient. After 30 minutes there is no apparent change at he injection site, but 36 hours later the patient reports that the area is red and swollen. This type of response is due to
A) type I hypersensitivity
B) type II hypersensitivity
C) type III hypersensitivity
D) type IV hypersensitivity
E) immunodeficiency
D
Which of the following statements is true of disinfectants?
A) they are effective in destroying endospores
B) they are used on inanimate surfaces
C) they are used on living tissue
D) they are used foe sterilization
E) they are only effective for short periods of time (seconds to minutes)
B
Which of the following statements regarding meiosis is MOST accurate?
A) Haploid cells produce diploid cells
B) meiosis has the same number of stages as mitosis
C) a diploid cell produces haploid daughter cells
D) Crossing over occurs during metaphase I
E) homologous ( non-sister ) chromatids separate during anaphase II
C
Recombination of genetic material between homologous chromosomes occurs during
A) metaphase of mitosis
B) early prophase I of meiosis
C) late prophase II of meiosis
D) prophase of mitosis
E) metaphase I of meiosis
B
Lipid-soluble molecules would be expected to cross the cytoplasmic membrane by which of the following processes?
A) facilitated diffusion
B) osmosis
C) diffusion
D) active transport
E) group translocation
C
IgE antibodies are best described as
A) the most common type of antibody in the blood during the initial phases of an immune response
B) a cause of basophil and eosinophil degranulation
C) the antibodies found in body secretions
D) those involved in complement activation
E) the trigger for antibody-dependent cellular toxicity ( ADCC).
B
Which of the following is an incorrect pairing?
A) electron beams; shorter wavelength
B) dark field; high contrast
C) magnification; refraction of radiation
D) numerical aperture; curved glass
E) contrast; staining techniques
D
The filamentous water molds are no longer classified with the true fungi because
A) they produce motile spores with two types of flagella
B) they have cell walls composed of chitin and are never diploid
C) their cell walls are composed of cellulose
D) they have cell walls composed of cellulose and motile spores with two flagella
E) they are never diploid
D
Leukocytes migrate to a site of infection in response to
A) chemokines
B) tumor necrosis factor (TNF)
C) interleukin 10 ( IL-10)
D) interferon alpha
E) bradykinins
A
Which of the following statements concerning glycolysis is TRUE?
A) glycolysis both requires the input of ATP and produces ATP
B) glycolysis produces ATP by oxidative phosphorylation
C) glycolysis occurs in the cell membranes of bacteria
D) glycolysis is an alternative to fermentation
E) Ribulose 5-phosphate is an intermediate of glycolysis
A
The anaerobic Clostridium species are troublesome pathogens in part because of their capacity for
A) high salt tolerance
B) rapid production
C) endospore production
D) oxygen production
E) biofilm production
C
DNA fingerprinting can be used
A) to generate cDNA clones
B) in forensic investigations
C) to detect unculturable organisms
D) to generate cDNA clones and libraries
E) for forensics and detection of unculturable organisms
E
The name systematic lupus erythematosus refers in part to the distinctive rash resulting from
A) autoantibodies causing mast cell degranulation
B) CTL attack on connective tissue fibroblasts
C) the release of histamines and kinins in response to sunburn
D) CTL attack on skin cells altered by sun damage
E) antibody-antigen complexes accumulating in the skin
E
A child has a history of repeated severe infections and frequently has recurring infections with the same bacterial pathogen. A blood sample shows some lymphopenia and serological tests are negative. Based on this information , which of the following is the likeliest diagnosis for this child?
A) hemolytic disease of the newborn
B) DiGeorge syndrome
C) severe combined immune deficiency (SCID)
D) systematic lupus erythematosus (SLE)
E) Bruton-type agammaglobulinemia
E
All of the following are ways in which cells regulate metabolism EXCEPT
A) synthesis or degradation of membrane transport proteins
B) use of the same coenzyme for anabolic and catabolic reactions that share substrate molecules
C) synthesis of a catabolic enzyme only when its substrate is available
D) isolation of various enzymes within membranous organelles
E) feedback inhibition by end products
B
A Petroff-Hauser counting chamber is a(N)
A) glass slide containing an etched grid for counting microbes directly using a microscope
B) apparatus that traps bacterial cells on a membrane filter where they can be counted
C) device used to count numbers of bacterial colonies on a Petri plate
D) device that counts cells as they interrupt an electrical current
E) device that measures the amount of light that passes through a culture
A
Which of the following is NOT a characteristic of Okazaki fragments?
A) they make up the lagging strand of replicated DNA
B) they are checked for accuracy by DNA polymerase III
C) they are joined together by DNA ligase
D) they begin with an RNA primer
E) they are longer in eukaryotic cells
E
Which of the following statements is TRUE of eosinophils?
A) they decline during allergic reaction
B) they secrete toxins onto the surface of helminth parasites
C) they produce the coating of a pathogen by compliment
D) they release prostaglandins and leukotrienes in response to microbes
E) they are intact skin, sebum, tears, etc.
B
A new antimicrobial medication prevents the assembly of ribosomes on mRNA. The new medication would be
A) an antisense RNA
B) a type of macrolide
C) a type of oxazolidinone
D) either an antisense RNA or a type of macrolide
E) either an antisense RNA or a type of oxazolidinone
E
Antigen-antibody complexes trapped in tissues and triggering complement activation or mast cell degranulation are characteristic
A) type I hypersensitivity
B) type II hypersensitivity
C) type III hypersensitivity
D) autoimmunity
E) graft rejection
C
Which of the following produces NADPH?
A) the pentose phosphate pathway only
B) the Entner-Doudoroff pathway only
C) the Embden-Meyerhof pathway only
D) both the Embden-Meyerhof and Entner-Doudoroff pathways
E) both the pentose phosphate and Entner-Doudoroff pathways
E
What factors need to be considered when choosing a method of microbial control?
A) the site and the environment to be treated
B) the environment of the site or material to be treated
C) the susceptibility of the microbes which must be removed
D) the site and environment to be treated, and the susceptibility of the microbes
E) the site or material to be treated
D
Precipitation assays involve the formation of immune complexes with ___ while agglutination tests involve agglutination of ____
A) soluble antigens; complement factors
B) soluble antibodies; insoluble complexes
C) soluble antigens; insoluble antigens
D) soluble antigens; large particles
E) insoluble antigens; soluble antigens
C
Which of the following statements regarding the cell-mediated immune response is TRUE?
A) cytotoxic T lymphocytes do not require presentation to become activated
B) cytotoxic T lymphocytes kill by producing hydrogen peroxide
C) cytotoxic T lymphocytes interact with antibodies that have bound antigen to identify their target
D) a single cytotoxic T lymphocyte can kill many target cells
E) Helper T lymphocytes have no role in the activation of cytotoxic T lymphocytes
D
An infectious disease researcher isolates the pathogen responsible for an emergency disease. The microbe is grown in the lab for many generations. A preparation of the laboratory- grown microbe is treated with ionizing radiation and then tested for its potential as a vaccine. What type of vaccine is this?
A) attenuated
B) subunit
C) toxoid
D) inactivated whole
E) combination
D
You are performing an experiment in your chemistry lab class. The directions advise caution because the reaction is exothermic. Which of the following is the hazard the directions warn about?
A) the reaction will generate enough light to require eye protection
B) the reaction will produce a noxious vapor
C) the reaction may cause the container to become dangerously hot
D) the reaction may cause the container to freeze and break
C
Several days after a walk in the woods, Cheryl develops a localized rash. It is not painful and soon fades so she thinks nothing of it . Several months later she experiences increasing fatigue, low grade fever, and pain in the joints. These symptoms persist for months before she seeks medical attention. This description is most consistent with a(n) ___ infection.
A) subclinical
B) acute
C) latent
D) asymptomatic
E) chronic
E
Recombinant DNA technology can be most accurately defined as the
A) study of genetic expression in microbes
B) selective breeding of organisms to create new combinations of traits
C) deliberate modification of the genome of an organism for practical purposes
D) use of microorganisms to produce useful products
E) study of replication and recombination in microbes
C
Graft rejection can be reduced by
A) antiphagocytic factors
B) preventing T cell proliferation
C) antihistamine
D) epinephrine
E) preventing B cell activation
B
Which of the following is the correct sequence of a diverse process?
A) incubation, prodromal period, illness, decline, convalescence
B) prodromal period, convalescence, incubation, illness, decline
C) illness, convalescence, incubation, prodromal period, decline
D) incubation, convalescence, prodromal period, illness, decline
E) convalescence, incubation, prodromal period, illness, decline
A
A CD4+ cell detects its epitope presented by an APC and receives IL- 4 signals. It will differentiate to become a(n)
A) Th2 cell
B) Th1 cell
C) CTL
D) Tr lymphocyte
E) APC
A
The role of dendrites in the adaptive immune response is to
A) attack and destroy invading pathogens
B) detect auto reactive lymphocytes and trigger apoptosis
C) degrade exogenous antigens fro presentation on MHC II molecules
D) process endogenous antigens for presentation on MHC I molecules
E) distinguish between endogenous ad exogenous antigens
C
Bacteria described as "Low G+C"
A) include filamentous Actinomycetes
B) have DNA composed of more than 50% AT pairs
C) Gram stain pink and are cocci
D) have unmethylated GC DNA
E) are Gram- negative Cyanobacteria
B
How is HIV provirus different from a lambda- phage prophage?
A) All the offspring of a cell infected with a prophage will contain the virus
B) Lambda phage-infected cells produce virus slowly over time
C) The HIV provirus is inactive inside the host cell
D) The HIV provirus is integrated permanently into the host cell's DNA
E) All subsequent generations of HIV- infected cells carry the provirus
D
The AUG codon functions in coding for the amino acid methionine and as a
A) termination signal
B) recognition site for RNA polymerase
C) start signal
D) marker for introns
E) "wobble" codon
C
The perforin- granzyme pathway involves
A) presenting the foreign antigen to B cells
B) binding CD95L to infected cells, which eventually leads to cell apoptosis
C) the synthesis of a cell- killing proteins that act on infected or abnormal cells
D) the production of antibodies toward the invading pathogen
E) the production of fever, which kills the pathogen
C
Which of the following could result in hemolytic disease of the newborn?
A) Rh- positive mother and Rh-negative father
B) Rh- positive mother and Rh-positive father
C) Rh-negative mother and Rh-positive father
D) Rh-negative mother and Rh-negative father
E) either Rh- positive mother and Rh- negative farther or Rh-negative and Rh-positive father
C
Structures and products of pathogens that immune cells detect and respond to are called
A) leukotrienes
B) prostaglandins
C) TLRs
D) PAMPs
E) NODs
D
Variolation was first used
A) to treat individuals exposed to hepatitis
B) to immunize the Chinese against smallpox
C) for research purposes in the twentieth century
D) to protect individuals against the plague during the Middle Ages
E) to spread smallpox throughout the Native American populations
B
A food product is labeled as having antioxidants. It may therefore contain
A) amino acids
B) vitamin B2 ( riboflavin)
C) vitamin C
D) vitamin E
E) vitamin C or E, or both
E
Hydrogen bonds are found in all of the following EXCEPT
A) in the DNA double helix between nucleotides
B) between phosphate in ATP
C) between the R groups of amino acids in proteins
D) in the structure of complex polysaccharides
E) between water molecules
B
In precipitation tests, maximum precipitation takes place when
A) the amount of the antibody exceeds the amount of the antigen
B) a complex solution of many antibodies is used
C) the amount of the antigen exceeds the amount of the antibody
D) a toxin is present
E) the amount of the antibody and the amount of the antigen are at optimal proportions
E
Wandering macrophages recognize microorganism by means of
A) NOD proteins
B) TLRs
C) lectins and C3 protein
D) lectins
E) both TLRSs and NOD protein
E