Ch 25

46) The process by which white blood cells ingest and kill bacteria is called A) exocytosis. B) transcription. C) phagocytosis. D) translation.

C) phagocytosis.

18) Capsules are particularly important for A) making bacteria more vulnerable to host defense mechanisms. B) making bacteria less pathogenic. C) protecting bacteria from host defense mechanisms. D) allowing bacteria to become more phagocytic.

C) protecting bacteria from host defense mechanisms.

9) Exotoxins are ________, but endotoxins are ________. A) lipopolysaccharide-lipoprotein complexes / proteins B) carbohydrates / proteins C) lipids / proteins D) proteins / lipopolysaccharide-lipoprotein complexes

D) proteins / lipopolysaccharide-lipoprotein complexes

Which cell structure is important in adherence? a.cell wall b.fimbria c.teichoic acid d.lipopolysaccharide

b.fimbria

Lysozyme is found throughout our bodies to protect us from infection. Some bacteria are able to evade this defense a.by deactivating the enzyme. b.by altering their plasma membrane. c.by altering their outer membrane. d.by altering their peptidoglycan.

d.by altering their peptidoglycan.

All of the following are enzymes that increase virulence EXCEPT a.proteases. b.nucleases. c.lipases. d.cellulases.

d.cellulases.

Botulinum toxin and tetanus toxin BOTH block the release of neurotransmitters, but botulinum toxin causes ________, whereas tetanus toxin causes ________. a.severe diarrhea / tissue necrosis b.tissue necrosis / severe diarrhea c.spastic paralysis / flaccid paralysis d.flaccid paralysis / spastic paralysis

d.flaccid paralysis / spastic paralysis

26) Which of the following is more likely to cause urinary tract infections? A) fimbriated strains of Escherichia coli B) non-fimbriated strains of Escherichia coli C) both fimbriated and non-fimbriated strains of Escherichia coli D) None of the answers are correct.

A) fimbriated strains of Escherichia coli

48) ________ are toxic proteins released from the pathogen during normal growth. A) Endotoxins B) Exotoxins C) Macrotoxins D) Microtoxins

B) Exotoxins

2) Which of the following is NOT a subunit of lipopolysaccharide (LPS)? A) O-specific polysaccharide B) lipid A C) core polysaccharide D) M protein

D) M protein

1) Pathogenicity is the ability A) of the host to inflict damage on the pathogen. B) of the host to resist damage by the pathogen. C) of the pathogen to inflict damage on the host. D) None of these are correct.

C) of the pathogen to inflict damage on the host.

29) Siderophores are A) molecules that aid directly in attachment to host cells. B) inorganic molecules that help in active transport. C) organic molecules that help pathogens take up iron. D) toxins that affect the gastrointestinal tract.

C) organic molecules that help pathogens take up iron.

17) An outer coat consisting of a dense, well-defined polymer layer surrounding a cell and used in attachment is called a A) capsule. B) cytoplasmic membrane. C) lipopolysaccharide layer. D) pilus.

A) capsule.

41) Which of the following is a major growth-limiting micronutrient that influences microbial growth? A) iron B) water C) vitamin K D) sugar

A) iron

22) Which of the following is NOT important for the adherence of bacteria to host tissues? A) lipopolysaccharides B) capsule C) adhesins D) slime layer

A) lipopolysaccharides

7) Tetanus toxin causes A) muscles to be unable to relax. B) muscles to be unable to contract. C) severe diarrhea. D) hemolytic uremic syndrome.

A) muscles to be unable to relax.

20) It is thought that attenuation occurs especially in a laboratory setting because A) nonvirulent or weakly virulent mutants grow faster in laboratory media when there is no selective advantage to virulence. B) pathogens lose virulence with age and survive longer in laboratory cultures. C) patients can be treated with drugs that induce attenuation. D) there is selection for more virulent strains in the laboratory

A) nonvirulent or weakly virulent mutants grow faster in laboratory media when there is no selective advantage to virulence.

43) The best term to describe the general process by which microorganisms cause diseases is known as A) pathogenesis. B) virulence. C) invasion. D) infection.

A) pathogenesis.

4) Diptheria toxin is a A) type of endotoxin. B) cytolytic toxin. C) AB toxin. D) superantigen toxin.

C) AB toxin.

36) ________ is a damage or injury to a host organism that impairs its function. A) Trauma B) Infection C) Disease D) Transmission

C) Disease

31) Which of the following is a reason that specific pathogens tend to infect specific tissues? A) Some tissues have receptors for microbes, but others do not. B) There are chemical and physical differences between tissues. C) Tissues with neutral pH are colonized but those with acidic or alkaline pH are not. D) Microbes preferentially target external tissues, such as skin, as the environment is more favorable for their growth than inside the body.

B) There are chemical and physical differences between tissues.

True or False: Endotoxins are the secreted products of living cells, whereas exotoxins are cell bound and released in large amounts ONLY when the cells lyse.

False

Growth of a microorganism after entering a host is called a.colonization. b.infection c.invasion. d.disease.

a.colonization.

Streptokinase works to ________ fibrin clots while coagulase works to ________ fibrin clots. a.dissolve / promote b.promote / dissolve c.form / bust d.promote / target

a.dissolve / promote

Organism X has an LD50 of 2 x 102, and organism Y has an LD50 of 3 x 104. Which organism is more virulent? a.organism X b.organism Y

a.organism X

Which of the following does NOT occur during the development of dental caries? a.Streptococcus mutansuses dextran to attach to teeth and gums. b.Oral microflora produce high concentrations of exoenzymes when sucrose is present. c.Lactic acid dissolves calcium phosphate, causing decalcification of the tooth enamel. d.Oral biofilm microflora produce high concentrations of organic acids.

b.Oral microflora produce high concentrations of exoenzymes when sucrose is present.

Which of the following toxins is NOT a cytolytic exotoxin? a.hemolysin b.Shiga toxin c.leukocidin d.phospholipase

b.Shiga toxin

________ can vary between strains of an organism depending on the ability to adhere, colonize, and invade a host. a.Attenuation b.Virulence c.Disease d.Infection

b.Virulence

Following exposure to a pathogen, events leading to disease—in the correct order—are a.adherence, virulence, invasiveness. b.adherence, invasion, infection, toxicity. c.invasion, adherence, virulence. d.invasion, adherence, toxicity, infection.

b.adherence, invasion, infection, toxicity.

Pathogens that can secrete ________ are more virulent because of the organisms potential to spread in the host. a.cellulase b.hyaluronidase c.urease d.nuclease

b.hyaluronidase

The ability of a pathogen to enter a cell, spread, and cause disease is termed a.pathogenesis. b.invasion. c.colonization. d.adherence.

b.invasion.

Patients that are HIV+ are at greater risk of ________ than the average population. a.cytolytic infections b.opportunistic infections c.latent infections d.virulent infections

b.opportunistic infections

Genes for antiphagocytic proteins, exotoxins, and adherence that are clustered together on a bacterial chromosome are called a.virulence islands. b.pathogenicity islands. c.infection islands. d.operons.

b.pathogenicity islands.

Receptors on the surface of pathogens that are made of glycoproteins and lipoproteins are called a.capsules. b.slime layers. c.adhesins. d.adhesives.

c.adhesins.

Because they are Gram negative, E. coli, Salmonella,and Shigella all produce a.exotoxins. b.cytolytic toxins. c.endotoxins. d.enterotoxins.

c.endotoxins.

Which of the following is NOT a physiological effect of endotoxin exposure? a.tissue necrosis b.hemorrhagic shock c.rapid increase in the numbers of lymphocytes d.fever

c.rapid increase in the numbers of lymphocytes

Pathogens that have entered the bloodstream and are producing toxins are the cause of a.toxemia. b.bacteremia. c.septicemia. d.viremia.

c.septicemia.

________ organisms are valuable in the production of vaccines. a.Infectious b.Pathogenic c.Virulent d.Attenuated

d.Attenuated

Adherence factors include ALL of the following EXCEPT a.capsules. b.fimbriae. c.flagella. d.lipopolysaccharide layers.

d.lipopolysaccharide layers.

Neisseria gonorrhoeae can cause infection by a.producing enzymes that degrade peptidoglycan. b.producing virulence factors that breakdown cellulose. c.producing enzymes that modify their cell wall to evade lysozyme. d.producing enzymes that destroy antibodies on the surface of mucosal cells.

d.producing enzymes that destroy antibodies on the surface of mucosal cells.

A bacterial infection becomes a disease when a.the growth of normal flora is inhibited. b.the immune system is triggered. c.the organisms attach to host cells. d.there is tissue damage that impairs host function.

d.there is tissue damage that impairs host function.

________ is the growth of microorganisms NOT normally present within a host. a.Disease b.Virulence c.Infection d.Pathogenicity

c.Infection

5) Decalcification of the tooth enamel is caused by A) lipopolysaccharide. B) dextrans. C) formic acid. D) lactic acid.

D) lactic acid.

37) Pathogenicity and virulence differ in that A) pathogenicity refers to the overall ability of a microbe to cause disease, whereas virulence refers to the ability of one microbe to cause disease relative to another. B) virulence refers to the overall ability of a microbe to cause disease, whereas pathogenicity refers to the ability of one microbe to cause disease relative to another. C) pathogenicity only refers to pathogens, whereas virulence refers to any microbe that can cause an infection. D) virulence only refers to pathogens, whereas pathogenicity refers to any microbe that can cause an infection.

A) pathogenicity refers to the overall ability of a microbe to cause disease, whereas virulence refers to the ability of one microbe to cause disease relative to another.

16) Influenza virus targets A) respiratory epithelium. B) gastrointestinal cells. C) oral cavity cells. D) throat epithelium.

A) respiratory epithelium.

15) Salmonella species use ________ to facilitate attachment to gastrointestinal tissue. A) type I fimbriae B) antiphagocytic proteins C) siderophores D) pili

A) type I fimbriae

10) An endogenous pyrogen is A) a chemical from the bacterial cell wall that causes fever. B) a chemical produced by a host's own immune system that causes fever. C) a chemical released by a bacterial cell that causes fever. D) a chemical produced within a bacterial cell that is released during cell division or at death of the bacterium, at which point it causes fever.

B) a chemical produced by a host's own immune system that causes fever.

19) The decrease or loss of virulence of a pathogen is referred to as A) aging. B) attenuation. C) disinfectivity. D) lethal dose.

B) attenuation.

11) Staphylococcus aureus produces ________, leading to fibrin clots that protect them from attack by host cells. A) collagenase B) coagulase C) lipase D) amylase

B) coagulase

27) Which of the following is NOT an example of an AB toxin? A) shiga-like toxin B) hemolysins C) botulinum toxin D) tetanus toxin

B) hemolysins

3) Staphylococcus aureus and Streptococcus pyogenes strains can produce ________ that cause the severe and sometimes life-threatening symptoms of toxic shock syndrome. A) endotoxin B) superantigen toxins C) AB toxins D) cytolytic

B) superantigen toxins

39) What is the difference between adherence and colonization? A) Colonization occurs when transient microbes are on a tissue, whereas adherence is a more permanent attachment to cells. B) Colonization occurs when microbes begin to spread in host tissues, whereas adherence occurs when microbes initially attach. C) Colonization occurs when microbes begin to spread in host tissues, whereas adherence occurs when microbes first begin to reproduce in the host tissues. D) Colonization occurs when a microbe begins to grow in host tissues whereas adherence occurs when the microbe initially attaches.

D) Colonization occurs when a microbe begins to grow in host tissues whereas adherence occurs when the microbe initially attaches.

30) Cytolytic toxins A) are extracellular proteins. B) cause cell lysis and death. C) damage host cytoplasmic membrane. D) are extracellular proteins that cause cell lysis and death by damaging the host cytoplasmic membrane.

D) are extracellular proteins that cause cell lysis and death by damaging the host cytoplasmic membrane.

Exotoxins classified as AB toxins damage cells by a.using the B subunit to attach to the target cell while the A subunit enters and inhibits protein synthesis. b.using the A subunit to attach to the target cell while the B subunit enters and inhibits protein synthesis. c.using the A subunit to attach to the target cell while the B subunit enters and inhibits DNA synthesis. d.using the B subunit to attach to the target cell while the A subunit enters and inhibits DNA synthesis.

a.using the B subunit to attach to the target cell while the A subunit enters and inhibits protein synthesis.