HW for Exam 3 Ch.18, 24, 25

It is estimated that each healthy human can synthesize approximately _____ different antibodies. The first step in making a specific antibody occurs during the formation of a B cell from a progenitor stem cell (progenitor B cell) in bone marrow, _____ a foreign antigen is encountered.

10^11, before

Alphaproteobacteria of the genus _____ cause the formation of galls on plants, such as the one seen here. But when free-living in the soil, these same bacteria are subject to predation by the intracellular parasite _____ (also a proteobacterium).

Agrobacterium Bdellovibrio

Which cell type is best associated with humoral immunity? Choose one: A. B cells B. macrophages C. platelets D. T cells

B cells

Which of the following contains a plasma membrane receptor protein that interacts with antigen? Choose one: A. B cells only B. T cells only C. Both B cells and T cells D. Neither B cells nor T cells

Both B cells and T cells

Compare the classical complement pathway to the alternative complement pathway by sorting the properties into the appropriate bins. C1 complex cleaves two other complement factors, C2 and C4 Factor C3b binds to LPS Complement C1 protein complex binds to the Fc region of an antibody

Classical: C1 complex cleaves two other complement factors, C2 and C4 Complement C1 protein complex binds to the Fc region of an antibody Alternative: Factor C3b binds to LPS

Which genera of the Firmicutes phylum conduct fermentations of significant economical importance? Choose one or more: A.Listeria B.Staphylococcus C.Clostridium D.Mycoplasma E.Lactobacillus F.Enterococcus

Clostridium Lactobacillus

Lyme disease is caused by the bacteria Borrelia burgdorferi, which is transmitted through the bite of a tick. The mode of transmission for the B. burgdorferi pathogen is the _____ route. The portal of entry for B. burgdorferi is _____ .

Indirect vector parenteral

Typhoid Mary was a professional cook at the turn of the twentieth century who was an asymptomatic carrier of the bacteria Salmonella Typhi. She infected many people who ate at the eating establishments where she worked through contaminated food. The mode of transmission for the S. Typhi pathogen is the _____ route. The portal of entry for S. Typhi is _____ .

Indirect vehicle Oral

The bacterium Listeria monocytogenes enters a new host by: Choose one: A. sexual contact. B. inhalation of droplets. C. ingestion of contaminated food. D. tick bites. E. puncture wounds.

Ingestion of contaminated food

Once inside the host, how does Listeria evade phagocyte-mediated killing? Choose one: A. It has evolved resistance to host digestive enzymes. B. It prevents fusion of a phagosome with a lysosome. C. It uses a toxin to escape the phagosome. D. It produces a capsule which makes the cells difficult to phagocytose. E. It produces toxins that lyse host cells.

It uses a toxin to escape the phagosome

Which of the following is not a method used by microbes to interfere with MHC I antigen presentation on the surface of infected host cells? Choose one: A. inducing degradation of MHC molecules B. making a protein that induces TAP degradation C. making proteins that are not digested by host proteasomes D. making a protein that blocks the action of the TAP protein E. making a protein that increases the transport of the microbial antigen into the ER

Making a protein that increases the transport of the microbial antigen into the ER

Which of the following describes why the secondary immune response is much quicker and greater than the primary response to the same antigen? Choose one: A. Memory B cells are in place when the same antigen is encountered again. B. During the primary immune response, the antigen is quickly covered by antibody, slowing the response. C. T cells are involved in the secondary immune response but not during the primary response. D. Naive B cells are in excess and poised for a quick, strong secondary response

Memory B cells are in place when the same antigen is encountered again

Herd immunity is in place when _____ of the individuals within a population are vaccinated.

Most

Members of the phylum Actinobacteria have had a profound impact on human health over the course of civilization. One member of the genus _____ causes a deadly disease which has likely claimed over 1 billion victims, while another of the genus _____ yielded the first effective drug to combat this ancient scourge.

Mycobacteria Streptomyces

Imagine that a physician is treating a case of meningitis in a high school student. The responsible organism is proving difficult to culture, but preliminary DNA sequence analysis shows that it is a member of the Firmicutes phylum. The doctor confidently prescribes penicillin, and later vancomycin, neither of which result in any improvement in the patient's condition. Based on these results, the causative agent is most probably a species of _____ .

Mycoplasma

Rank the following biomolecules in order of increasing immunogenicity. Protein Nucleic acid Carbohydrate

Nucleic acid Carbohydrate Protein

The production of _____ by cyanobacteria is believed to have resulted in one of Earth's earliest mass extinctions.

O2

Imagine that you are an early microbiologist attempting to reproduce Louis Pasteur's famous experiments which helped disprove spontaneous generation. You first prepare a hay infusion (a type of nutrient broth), then boil it for 20 minutes in a swan-necked flask of the same design that Pasteur used. Upon cooling and incubation at room temperature, you notice that your broth has become cloudy (turbid) only a few days later. What did your broth contain that Pasteur's likely did not? Choose one: A. myxospores B. sufficient nutrients C. akinetes D. endospores E. hyperthermophilic archaea F. sufficient oxygen

endospores

Which of the following is a common virulence factor produced by Proteobacteria but is entirely lacking among Firmicutes pathogens? Choose one: A. endotoxin B. AB toxin C. enterotoxin D. cytotoxin E. neurotoxin

endotoxin

Some intracellular pathogens can use unipolar structures to mediate host cell actin polymerization. This gives the microbe motility within the host cell. In order for a pathogen to avoid being killed by the phagolysosome, which mechanism relies most upon motility? Choose one: A. escape of the phagosome B. living within the phagolysosome C. living within the lysosome D. inhibition of phagosome-lysosome fusion

escape of the phagosome

Verrucomicrobia contain cytoskeletal elements whose genes were likely acquired by transfer from what? Choose one: A. mycobacteria B. spirochetes C. archaea D. eukaryotes E. chlamydia

eukaryotes

The bacterial pathogens Salmonella and Shigella can live either inside a host cell or independently of a host cell. Such pathogens are known as what? Choose one: A. facultative intracellular pathogens B. obligate intracellular pathogens C. facultative extracellular pathogens D. obligate extracellular pathogens

facultative intracellular pathogens

Antigens coated in C3b are protected from phagocytosis. This statement is _____ .

false

Which of the following information could not be gained from a genomic study of a pathogenic strain and a nonpathogenic strain of the same species of bacteria?Choose one: A. genes that are expressed when the pathogenic bacteria infect a host B. lack of metabolic genes in both strains that would make them hard to grow in culture C. presence of pathogenicity islands in the pathogenic strain D. identity of possible virulence genes present in the pathogenic strain but not present in the nonpathogenic strain 1st attempt

genes that are expressed when the pathogenic bacteria infect a host

Imagine that you are examining a culture of Anabaena and observe clusters of bacteria surrounding the larger differentiated cells that occur at regular intervals along the filaments. These bacteria are probably: Choose one: A. growing on organic compounds leaked from the cyanobacterium. B. harvesting light wavelengths not absorbed by the cyanobacteria. C. acting as antennae to funnel photons to cyanobacterial photosystems. D. pathogenic and causing the nearby cells to lyse. E. nodulating nitrogen-fixing bacteria.

growing on organic compounds leaked from the cyanobacterium

A(n) _____ is a small compound that must be conjugated to a larger carrier antigen to elicit the production of an antibody.

hapten

The immune response to smallpox will not protect someone against the plague bacillus (Yersinia pestis). Which of the following best describes this idea? Choose one: A. immunological specificity B. threshold dose C. major histocompatibility complex D. B-cell tolerance

immunological specificity

The outer membrane of Gram-negative bacteria contains lipopolysaccharide (LPS). When the Gram-negative bacterium dies, it releases LPS, which activates an immune reaction. The immune reaction can cause symptoms ranging from fever to shock to death. Because of the severe immune reaction elicited by free LPS, it is called an endotoxin. The effects caused by endotoxin are known as which of the following? Choose one: A. immunopathogenesis B. infection cycle C. Koch's postulates D. pathogen effects

immunopathogenesis

Herd immunity protection __________ as more individuals are vaccinated. Choose one: A. remains the same B. increases C. decreases

increases

If a patient has been diagnosed with human immunodeficiency virus (HIV), then part of their _____ immunity is not functioning properly.

innate and adaptive

A mutant strain of Listeria that failed to polymerize actin would be less able to: Choose one: A. direct host cell motility. B. detoxify digestive enzymes. C. survive in the cytoplasm. D. multiply in the cytoplasm. E. invade neighboring cells.

invading neighboring cells

The two major genera of Gram-positive bacteria include the _______________ , which contains the endospore-forming genera (e.g., Bacillus and Clostridium), and the _______________, which contains some filamentous forms (e.g., Streptomyces) that produce exospores. Choose one: A. low GC Actinobacteria ; high GC Firmicutes B. high GC Actinobacteria ; low GC Firmicutes C. low GC Firmicutes ; high GC Actinobacteria D. high GC Firmicutes ; low GC Actinobacteria

low GC Firmicutes; high GC Actinobacteria

Which eukaryote-like organelles have been observed in Planctomycete cells? Choose one: A. flagella composed of microtubules B. chloroplasts C. membrane-bound "nucleus" containing DNA D. mitochondria E. Golgi apparatus

membrane-bound "nucleus" containing DNA

Which of the following is not among the common types of vaccines? Choose one: A. microbial cell nucleic acids B. attenuated-strain microbes C. heat-killed intact microbes D. microbial cell surface proteins

microbial cell nucleic acids

The preepidemic strain was less virulent than the epidemic strain. After the promoter controlling the two genes was mutated back to the preepidemic sequence, the amount of the SPN and SLO proteins decreased, as shown in the figure. The data therefore indicate that the SPN and SLO proteins are virulence factors according to which of the following? Choose one: A. Koch's postulates modified for viruses B. molecular Koch's postulates C. statistical analysis D. Koch's postulates

molecular Koch's postulates

Alphaproteobacteria such as Nitrobacter winogradsky play a key role in the global cycling of nitrogen. This organism is a lithotroph that oxidizes nitrite to _____for growth.

nitrate

A subunit vaccine will elicit what type of response? Choose one: A. only an antibody response B. only a T-cell response C. both an antibody and a T-cell response D. neither an antibody nor a T-cell response

only an antibody response

Superantigens exert their toxic effects by doing what? Choose one: interfering with protein synthesis causing selective destruction of helper T cells disrupting cell-cell adherence causing nonspecific damage to cell membranes overstimulating the immune response

overstimulating the immune response

What does the term "immunogenicity" refer to?Choose one: A. the rate at which invading bacterial cells divide and cause disease B. the time required for one human to transmit disease to another C. the culmination of the various signs and symptoms of disease D. the effectiveness with which an antigen elicits an immune response

the effectiveness with which an antigen elicits an immune response

More than one type of major histocompatibility complex proteins is integral to T-cell physiology. This statement is _____ .

true

T cells never bind to free-floating antigen. This statement is _____ .

true

A species within the genus Deinococcus is famous for its ability to: Choose one: A. supplement heterotrophy with anoxygenic phototrophy. B. cause disease in humans. C. generate methane by a form of anaerobic respiration. D. withstand high doses of radiation and extreme dryness. E. grow at temperatures approaching boiling.

withstand high doses of radiation and extreme dryness

Planctomycetes most closely resemble _____ in their form of cell division.

yeast

Which of the following best describes affinity maturation?Choose one: A. Only B cells with the strongest binding antibodies as part of their B-cell receptors will remain activated. B. Only T cells with the strongest binding antibodies as part of their T-cell receptors will remain activated. C. The class changing from IgM production to other antibody isotypes will occur after naive B cells bind their target antigen. D. The rapid selection and proliferation of a subset of B cells will occur during the primary or secondary antibody response.

Only B cells with the strongest binding antibodies as part of their B-cell receptors will remain activated

A pathogenic bacterium has a low lethal dose 50% (LD50). Which of the following statements about the bacteria is true? Choose one: A. Only a few of the bacteria are required to kill 50% of infected hosts. B. A small dose of an antibiotic drug is sufficient to kill the bacteria. C. The bacteria have a high infectious dose 50% (ID50). D. The bacteria have a low virulence.

Only a few of the bacteria are required to kill 50% of infected hosts

Primary pathogen, opportunistic pathogen, and reservoirs are terms used to describe infections and infection cycles. Sort the descriptions of these terms to the correct box below. Staphylococcus aureus can infect wounds in surgery patients Includes birds for the eastern equine encephalitis virus Yersinia pestis can survive in macrophages because it prevents lysosome/phagosome fusion in macrophages Requires a compromised host Harbors the infectious microbe Can breach the healthy host's defenses

Primary Pathogen: Yersinia pestis can survive in macrophages because it prevents lysosome/phagosome fusion in macrophages Can breach the healthy host's defenses Opportunistic Pathogen: Requires a compromised host Staphylococcus aureus can infect wounds in surgery patients Reservoir: Harbors the infectious microbe Includes birds for the eastern equine encephalitis virus

Which Gram-negative phylum contains the most metabolic diversity of any phylum and the largest number of described species? Choose one: A. Bacteroidetes B. Proteobacteria C. Nitrospirae D. Fusobacteria E. Acidobacteria

Proteobacteria

Which of the following is NOT a disease caused by spirochetes?Choose one: A. syphilis B. Rocky Mountain spotted fever C. leptospirosis D. Lyme disease E. relapsing fever

Rocky Mountain spotted fever

Which of the following proteins is not used by pathogens to attach to the host? Choose one: A. fimbriae B. Type I pili C. viral envelope proteins D. FimH proteins E. SecA proteins F. adhesins G. viral capsid proteins H. Type IV pili

SecA proteins

Which of the following are pathogenic species within the Firmicutes phylum? Choose one or more: A.Staphylococcus aureus B.Lactobacillus lactis C.Streptococcus pyogenes D.Epulopiscium fishelsoni E.Salmonella enterica F.Clostridium botulinum

Streptococcus pyogenes Clostridium botulinum

Which of the following is consistent with the data presented in the image of the rhinovirus? Choose one: A. The antibody-coated rhinovirus cannot attach to a host cell because antibodies are interacting with cellular proteins that are involved in viral adhesion. B. The antibody-coated rhinovirus cannot attach to a host cell because antibodies are interacting with viral proteins that are involved in cellular adhesion. C. The non-antibody-coated rhinovirus cannot attach to a host cell because antibodies are being produced by that host cell and thereby blocking attachment. D. The non-antibody-coated rhinovirus can attach to this host cell because this host cell is already infected by a virus and a viral protein is being expressed on the cellular surface.

The antibody-coated rhinovirus cannot attach to a host cell because antibodies are interacting with viral proteins that are involved in cellular adhesion

The pathogenic strain has an LD50 of 400 and the mutant strain has an LD50 of 1,200. Which of the following statements about the gene is true? Choose one: A. The gene has been eliminated as a candidate for a virulence gene because the removal of the gene increased the virulence of the mutant strain. B. The gene is still a candidate for a virulence gene because the removal of the gene decreased the virulence of the mutant strain. C. The gene has been eliminated as a candidate for a virulence gene because the removal of the gene decreased the virulence of the mutant strain. D. The gene is still a candidate for a virulence gene because the removal of the gene increased the virulence of the mutant strain.

The gene is still a candidate for a virulence gene because the removal of the gene decreased the virulence of the mutant strain

How do phagocytes overcome the immune protection that the bacterial capsule gives to pathogens? Choose one: A. They bind to the Fc region of antibodies that opsonize the capsule. B. They recognize bacterial cell-surface structures. C. They release proteins that trigger apoptosis in the pathogen. D. They bind to C3b complement factor on the surface of the capsule.

They bind to the Fc region of antibodies that opsonize the capsule

Which of the following statements about virulence factors is true? Choose one: A. They always activate host defenses. B. They increase the ability of a pathogen to cause disease. C. They are defined as being any genes that are required for microbial survival. D. They are found in nonpathogenic strains of a microbe as well as pathogenic strains.

They increase the ability of a pathogen to cause disease

What characteristic of V. cholerae allows it to cause widespread epidemics? Choose one: A. V. cholerae spreads through numerous vectors, including specific mosquito species that can fly great distances. B. V. cholerae spreads mainly through airborne droplets. C. V. cholerae is spread through person-to-person contact. D. V. cholerae can survive in marine environments and can thereby spread to many areas where people live.

V. cholerae can survive in marine environments and can thereby spread to many areas where people live.

Which of the following is correct regarding vaccines and human health? Please restrict your answers to address only biological facts. Choose one: A. Vaccines may initially elicit a fever and mild infection. B. Vaccines have been scientifically linked to autism. C. Serious health side effects from immunizations, like diabetes, are common. D. The risks associated with vaccination far outweigh the benefits.

Vaccines may initially elicit a fever and mild infection

Most mandated vaccines are administered during _____ , and when multiple doses are administered, then those multiple doses are referred to as _____ .

childhood, boosters

In a process called __________, an invading antigen binds to a B cell and that B cell then proliferates to large numbers and differentiates into antibody-producing plasma cells or memory B cells. Choose one: A. antigen presentation B. opsonization C. clonal selection D. denaturation

clonal selection

The cholera toxin, an AB exotoxin, attaches an ADP-ribose group to the host's stimulatory G factor (Gs). The normal function of Gs is to stimulate the host's adenylate cyclase, which produces the second messenger molecule cAMP. This toxin-mediated ADP-ribosylation of Gs has which of the following effects? Choose one: A. constant activation of Gs, causing an increase in cAMP levels and resulting in decreased ion transport from the infected host cell B. inactivation of Gs, causing a decrease in cAMP levels and resulting in increased ion transport from the infected host cell C. constant activation of Gs, causing an increase in cAMP levels and resulting in increased ion transport from the infected host cell D. inactivation of Gs, causing a decrease in cAMP levels and resulting in decreased ion transport from the infected host cell

constant activation of Gs, causing an increase in cAMP levels and resulting in increased ion transport from the infected host cell

Mycobacterium tuberculosis infects the lungs and can spread to other organs from the lungs. When an infected individual coughs, the bacteria can enter the air and infect nearby individuals. The mode of transmission for the M. tuberculosis pathogen is the _____ route. The portal of entry for M. tuberculosis is _____ .

direct airborne respirtory

The C3a, C4a, and C5a cleavage fragments generated by the complement cascade _____ in MAC formation. These fragments generated by the complement cascade _____ important for amplifying the immune reaction.

do not participate, are

The influenza virus attaches to host sialic acid molecules through the hemagglutinin envelope protein. The host sialic acid molecules are linked to the carbohydrate galactose on the surface of the host cell. The hemagglutinin of avian influenza strains binds preferentially to sialic acid in the α-2,3 linkage conformation. The hemagglutinin of human influenza strains binds preferentially to sialic acid in the α-2,6 linkage conformation. Which of the following would decrease the ID50 of the avian influenza virus for human cells?Choose one or more: A.A variation in certain human individuals causes an increase in their α-2,3-linked sialic acid. B.A mutation allows the avianhemagglutinin to bind sialic acid in the α-2,3 linkage conformation with greater efficiency. C.A mutation allows the avian hemagglutinin to bind sialic acid in the α-2,6 linkage conformation with greater efficiency. D.A variation in certain human individuals causes a decrease in their α-2,6-linked sialic acid. E.A mutation causes the avian hemagglutinin to bind sialic acid in the α-2,3 linkage conformation with less efficiency. F.A variation in certain human individuals causes an increase in their α-2,6-linked sialic acid.

A variation in certain human individuals causes an increase in their α-2,3-linked sialic acid. A mutation allows the avian hemagglutinin to bind sialic acid in the α-2,6 linkage conformation with greater efficiency.

Which of the following are examples of virulence factors?Choose one or more: A.DNA polymerase of Mycobacterium tuberculosis that replicates the bacterial DNA B.botulinum toxin produced by Clostridium botulinum that blocks host nerve transmission C.Rubisco enzyme that fixes carbon dioxide in cyanobacteria D.hemagglutinin envelope protein on the surface of the influenza virus that binds to a receptor on the surface of host cells E.Rab1b protein in Yersinia pestis that prevents the fusion of lysosomes and phagosomes in host macrophages F.capsule of Neisseria meningitidis that prevents phagocytes from adhering to the bacteria

Botulinum toxin produced by Clostridium botulinum that blocks host nerve transmission Hemagglutinin envelope protein on the surface of the influenza virus that binds to a receptor on the surface of host cells Rab1b protein in Yersinia pestis that prevents the fusion of lysosomes and phagosomes in host macrophages Capsule of Neisseria meningitidis that prevents phagocytes from adhering to the bacteria

The cholera toxin, an AB exotoxin, creates a(an) _____ environment in the intestinal lumen when compared to the cytoplasm of the intestinal cells.

Hypertonic

There are nine different functional categories of exotoxins. Match each of the five exotoxins described below with its category by dragging it to the appropriate box. Cytoskeleton, Cell Cycle, Cell-Cell Adherence, Vesicle Traffic, Exocytosis Helicobacter pylori VacA toxin causes vacuolization with the host cell Vibrio cholera RTX toxin depolymerizes actin Tetanus toxin prevents the release of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) Staphylococcus aureus exfoliative toxin breaks the connections between the dermis and the epidermis E. coli cytolethal distending toxin (CLDT) interrupts host cell division

Cytoskeleton: Vibrio cholera RTX toxin depolymerizes actin Cell Cycle: E. coli cytolethal distending toxin (CLDT) interrupts host cell division Cell-Cell Adherence: Staphylococcus aureus exfoliative toxin breaks the connections between the dermis and the epidermis Vesicle Traffic: Helicobacter pylori VacA toxin causes vacuolization with the host cell Exocytosis: Tetanus toxin prevents the release of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA)

Below are characteristics of the type III secretion systems used by the pathogenic E. coli strains and characteristics of those used by S. enterica. There are also characteristics that apply to both species of pathogen. Sort the secretion system characteristics by dragging them to the appropriate box. E. coli, S. enterica, Both Result(s) in the tight binding between the bacteria and the host cell required for pathogenesis Prevent(s) the fusion of the phagosome and the lysosome Result(s) in the reorganization of the host cell cytoskeleton Allow(s) the bacteria to avoid engulfment by host cells Result(s) in engulfment of the bacteria by the host cell Genes for the secretion system are found on pathogenicity islands within the bacterial genome Lead(s) to the formation of a membrane pedestal on the surface of the host cell

E. coli: Allow(s) the bacteria to avoid engulfment by host cells Result(s) in the tight binding between the bacteria and the host cell required for pathogenesis Lead(s) to the formation of a membrane pedestal on the surface of the host cell S. enterica: Result(s) in engulfment of the bacteria by the host cell Prevent(s) the fusion of the phagosome and the lysosome Both: Result(s) in the reorganization of the host cell cytoskeleton Genes for the secretion system are found on pathogenicity islands within the bacterial genome

Which of the following best describes antibody structure and function? Choose one: A. Each antibody has one variable region that is specific to only one antigen. B. Each antibody has two variable regions that are both specific to the same antigen. C. Each antibody has one variable region that is specific to multiple antigens. D. Each antibody has two variable regions that are each specific to different antigens.

Each antibody has two variable regions that are both specific to the same antigen

Endotoxins and exotoxins are both bacterial virulence factors that can affect the infected host. Sort the following descriptions as to whether they apply to endotoxins, exotoxins, or both Composed of protein Component of lipopolysaccharide Are virulence factors Secreted by living cells Harm the host by overstimulating the host's immune defense Include hemolysins Released by dead cells Produced by Gram-negative bacteria Produced by Gram-positive bacteria

Endotoxins: Released by dead cells Harm the host by overstimulating the host's immune defense Component of lipopolysaccharide Exotoxins: Secreted by living cells Composed of protein Include hemolysins Produced by Gram-positive bacteria Endotoxin and Exotoxin: Are virulence factors Produced by Gram-negative bacteria

Which of the following exotoxins does not disrupt membranes? Choose one: A. Escherichia coli labile toxin B. Staphylococcus aureus alpha toxin C. Streptococcus pyogenes streptolysin O D. Clostridium perfringens phospholipase C E. Listeria monocytogenes listeriolysin

Escherichia coli labile toxin

Which of the following statements about herd immunity is correct? Choose one: A. Herd immunity is only effective against viral diseases as bacterial transmission is exempt. B. Herd immunity will provide protection against tetanus provided many people have the DTaP vaccine. C. Herd immunity will not protect against an unvaccinated person acquiring a deadly disease from a sick person. D. Relying only on herd immunity as protection is a good way to ensure that you will not become ill.

Herd immunity will not protect against an unvaccinated person acquiring a deadly disease from a sick person.

The pathogenic strain of Escherichia coli, E. coli O104:H4, expresses the Shiga toxin and is highly resistant to many antibiotics. How did the E. coli O104:H4 strain originally obtain the genes for the Shiga toxin and antibiotic resistance?Choose one: A. random mutation B. vertical transmission C. immunopathogenesis D. horizontal gene transfer

Horizontal gene transfer

Which of the following immunoglobulin gene segments contribute to genetic diversity?Choose one or more: V regions J regions C regions D regions

V regions, J regions, D regions

Staphylococcus aureus uses a cell wall protein, protein A, to avoid immune detection. To which of the following does protein A bind to prevent phagocyte recognition of S. aureus? Choose one: A. C3b complement factor B. Fc region of antibodies C. receptors on the phagocyte D. capsule polysaccharides

Fc region of antibodies

Pathogenicity islands are segments of the chromosomes of pathogenic bacteria. They contain clusters of virulence genes and are thought to be acquired by the bacteria through horizontal gene transfer. Which of the following are common characteristics of these pathogenicity islands?Choose one or more: A.flanked by genes that are homologous to phage or plasmid genes B.contain "housekeeping" genes that are required for bacterial viability C.have a GC/AT ratio that is different from the rest of the chromosome D.contain an inverted repeat sequence E.linked to a tRNA gene F.flanked by sequences recognized and cut by restriction enzymes

Flanked by genes that are homologous to phage or plasmid genes Have a GC/AT ratio that is different from the rest of the chromosome Linked to a tRNA gene

Order the steps of antibody production from start to finish. Naive B cells leave the bone marrow Activated B cells differentiate into plasma cells B cells encounter foreign antigen with specificity for their particular antibody Gene rearrangements determine the antibody specificity of any given B cell Antibodies specific to a foreign antigen are produced and secreted

Gene rearrangements determine the antibody specificity of any given B cell Naive B cells leave the bone marrow B cells encounter foreign antigen with specificity for their particular antibody Activated B cells differentiate into plasma cells Antibodies specific to a foreign antigen are produced and secreted

Sort the following properties as pertaining to helper T cells only, cytotoxic T cells only, or neither helper nor cytotoxic T cells. Bind viral antigens present on any virus-infected cell Bind only to antigens attached to MHC surface proteins on APCs Produce antibodies directly

Helper T cells: Bind only to antigens attached to MHC surface proteins on APCs Cytotoxic T cells: Bind viral antigens present on any virus-infected cell Neither Cell Type: Produce antibodies directly

Many filamentous cyanobacteria (e.g., Oscillatoria seen here) disperse by producing short chains of cells known as _____ , while other species (e.g., Anabaena) can also produce _____ in response to adverse environmental conditions.

Hormogonia akinetes

Through a search of the genetic databases it is found that a protein expressed by a microbial pathogen resembles a host protein. What is this resemblance most likely to indicate? Choose one: A. The microbial protein mimics the host protein's function. B. The microbial protein binds to the similar host protein. C. The microbial protein is not a virulence factor. D. The microbial protein is in the same location as the host's protein.

The microbial protein mimics the host protein's function

A child was exposed to a disease-causing virus (most likely chicken pox from the Varicella zoster virus) when he was 5 years old. At 12 years old, the child encounters the same virus again. What is most likely expected to happen? Choose one: A. The child will be administered antibiotics immediately to remove the disease-causing pathogen. B. The pathogen will be neutralized with antibody quickly and the virus will be cleared before symptoms develop. C. After a short lag phase, the child will mount an immune response and serum antibody concentration will increase. D. Since macrophages already acted against the pathogen, they will engulf the virus immediately upon exposure.

The pathogen will be neutralized with antibody quickly and the virus will be cleared before symptoms develop

What do the following infections have in common: periodontitis, recurrent tonsillitis, chronic otitis media, and osteomyelitis?Choose one: A. They respond well to antimicrobial drugs. B. They are caused by bacterial biofilms. C. They are caused by the same bacterial species. D. They are easily cleared by the host's defenses.

They are caused by bacterial biofilms

With only a few exceptions, which of the following are true of all known species of spirochetes? Choose one or more: A.They are pathogenic. B.They grow as multicellular filaments. C.They exhibit gliding motility. D.They are heterotrophic. E.They have "Gram-negative" cell walls. F.They have long helically coiled cells.

They are heterotrophic They have "gram-negative" cell walls They have long helically coiled cells

Imagine that you have isolated what appears to be a new species of thermophile from a microbial mat at Yellowstone National Park. This organism can grow up to 90ºC and contains ether-linked lipids in its plasma membrane. Using whole-genome sequence data, your team pieces together a single circular chromosome—about half the size of the one in E. coli. About 54% of its genes have functional assignments, but there is an interesting pattern in their biological roles. Specifically, genes required for transcription and translation are most like bacterial orthologues, while genes encoding nutrient transporters and electron transport proteins are most similar to thermophilic archaea. What is the best interpretation of your data? Choose one: A. This is an archaeon which has taken up large segments of bacterial DNA. B. This is an evolving endosymbiosis between an archaeal host and internalized bacterium. C. You have isolated a type of primitive thermophilic eukaryote. D. The cultures you made of this organism contain codependent bacteria and archaea. E. This is a bacterium which has acquired a surprisingly large number of archaeal genes.

This bacterium which has acquired a surprisingly large number of archaeal genes

The pathogen Listeria monocytogenes produces exotoxins that disrupt membranes. What is the purpose of the membrane disruption caused by Listeria monocytogenes? Choose one: A. to produce signaling molecules that activate host cell cytokine production B. to kill the host cell C. to increase the permeability of the host's capillaries in order to increase nutrient availability to the bacteria D. to allow the bacteria to escape the phagosome and grow in the cytoplasm of the host

To allow the bacteria to escape the phagosome and grow in the cytoplasm of the host

If the gene is still considered a candidate virulence gene, what would be the next step to confirm that this is indeed the case? Choose one: A. Link the candidate gene to the GFP gene so that the protein is fluorescently tagged and can be located within the host cell. B. Transform the mutant bacterial strain with a plasmid containing the candidate gene. C. Infect human hosts with the mutant bacterial strain. D. Genetically modify a different genus of bacteria to express the candidate gene.

Transform the mutant bacterial strain with a plasmid containing the candidate gene

Which of the following traits of bacterial cells differ significantly from the other domains of life?Choose one or more: A.translation elongation factors B.phospholipids in membrane C.type of RNA polymerase D.DNA as genetic material E.peptidoglycan in cell envelope F.nature of genetic code

Translation elongation factors peptidoglycan in cell envelope

T cells are activated only by antigen bound to another cell's surface. This statement is _____

True

The gamma class of the Proteobacteria includes many medically important genera in the families Enterobacteriaceae and Pseudomonadaceae. Which of the following characteristics allows differentiation between these two groups? Choose one: A. ability to form biofilms B. ability to grow anaerobically C. Gram reaction D. ability to grow autotrophically E. morphology (rods versus cocci)

ability to grow anaerobically

Which of these types of immunity includes the other two types? Choose one: A. adaptive immunity B. cell-mediated immunity C. humoral immunity D. None of these types of immunity is related to another type.

adaptive immunity

Within the immune cell interaction shown in Part 1, which of the following types of immunity are shown? Choose one or more: A.innate B.adaptive C.humoral D.cell-mediated

adaptive, humoral, cell-mediated

Blocking hypermutation would prevent which of the following?Choose one: A. light-chain VJ rearrangement B. affinity maturation C. heavy-chain VDJ rearrangement D. isotype class switching

affinity maturation

Nitrosomas spp. are betaproteobacteria which mediate which important step in the nitrogen cycle? Choose one: A. ammonification B. denitrification C. nitrate reduction D. nitrite oxidation E. ammonia oxidation

ammonia oxidation