Ch. 27 review
a
Certain traits that allow pathogens to create infection and cause disease are termed a. virulence factors. b. collagenases. c. hyaluronidases. d. streptokinases.
d.
antibodies interact with which innate defenses? a. Phagocytosis, inflammation, and the complement system b. The complement system c. First-line defenses d. Phagocytosis and the complement system e. Inflammation f. Phagocytosis
c
Factors that enhance an organism's ability to adhere to host tissues include __________. a. lipopolysaccharide b. peptidoglycan c. fimbriae d. adherence enzymes
c
How are immune cells able to detect foreign pathogens? a. They detect foreign, unfamiliar chemical substances released by the invading cells. b. They can compare the DNA sequences from the foreign cells to host DNA. c. They are able to detect structures on the surfaces of foreign cells that are not found in the host.
b.
How are superantigens different from other types of exotoxins? a. Superantigens are comprised of two functional domains. b. Superantigens cause an overstimulation of the host immune system. c. Superantigens only act against host neurons. d. Superantigens must be endocytosed into a target cell before becoming active.
c
How can capsules enable bacteria to evade the immune system? a. Capsules can bind up IgA, rendering it inactive. b. A capsule is a superantigen that distracts the immune system. c. Capsules block the complement biding sites on the surface of the pathogen.
d
Mucous membranes are a part of a. the complement system. b. adaptive defense. c. humoral immunity. d. innate defense. e. cell-mediated immunity.
false
T/F? Cholera begins following a bite from a mosquito.
true
T/F? Clostridium botulinum are endospore-forming bacteria normally found in the soil.
True
T/F? Endotoxins are released in large amounts only when cells lyse.
False
T/F? Gram-positive bacteria produce endotoxins.
false
T/F? Normal microflora are usually found in the blood, lymph, and nervous systems of the body.
false, endotoxins
T/F? The toxic lipopolysaccharides produced by MOST gram-negative bacteria are called exotoxins.
true
T/F? Vaginal acidity in the adult female is due to acid production by Lactobacillus acidophilus.
b
The process by which white blood cells ingest and kill bacteria is called a. translation. b. phagocytosis. c. transcription. d. exocytosis.
d
Virulence factors that enhance invasiveness of a pathogen can include __________. a. exotoxins b. coagulase c. collagenase d. all of the above
a
Virulence is the relative ability of a ________ to cause disease. a. pathogen b. bacterium c. commensal d. virus
c
What are leukocidins? a. Molecules that can degrade IgA b. Molecules that destroy the complement proteins c.Molecules that are capable of destroying phagocytes
b.
What does the minimum inhibitory concentration (MIC) of a chemical tell you? a. It tells you the smallest concentration of the chemical that is needed to kill a specific microorganism. b. It tells you the smallest concentration of the chemical that is needed to inhibit the growth of a specific microorganism. c. It tells you the smallest concentration of an organism that is needed for chemical control. d. It tells you the smallest concentration of the chemical that is needed to inhibit the growth of any microorganism.
d
When would endotoxins be released from a bacterial cell? a. When the cell moves toward a energy source b. When the cell attaches to a host cell in the human body c. During bacterial conjugation d. When the cell dies
b.
Which cells directly attack abnormal cells in the body? a. B cells b. Cytotoxic T cells c. Phagocytes d. Helper T cells
a
Which domain of the A-B toxin binds to cell surface receptors on the host cell? a. B domain b. A domain c. A-B toxins do not bind to cell surfaces. d. Both the A and B domains have the ability to bind to cell surface receptors.
a.
Which of the following are NOT found in the gastrointestinal tract of healthy humans? a. protists b. Escherichia coli c. Bacteroides d. Clostridium
d.
Which of the following defense systems would be involved in fighting a viral pathogen? a. Phagocytosis b. Humoral immunity c. Complement system d. T lymphocytes
a.
Which of the following does NOT affect pathogen growth? a. doubling time b. temperature c. availability of microbial nutrients d. pH
d
Which of the following environmental and host factors influence the composition of resident microflora on the skin? a. age b. weather c. personal hygiene d. all of the above
C
Which of the following enzymes breaks down the "glue" that holds cells together? a. Collagenase b. Streptokinase c. Hyaluronidase d. Fibrinolysin
d.
Which of the following is an important virulence factor for dental caries? a. siderophores b. pili c. endotoxin d. polysaccharide adhesion
a
Which of the following would be the first sign of an infection that resulted in the release of endotoxin? a. Fever b. Pain c. Nausea d. Weakness
C
Which of these microorganisms is MOST likely to be found in the human gut? a. Roseobacter denitrificans b. Streptococcus mutans c. Helicobacter pylori d. Streptococcus sobrinus
d.
Why is a release of endotoxin into the bloodstream potentially deadly? a. Endotoxin can quickly enter the brain from the bloodstream, causing brain damage. b. It results in dehydration of the patient. c. It causes necrosis of the liver. d. It can lower blood pressure and cause the patient to go into shock.
a
First line defenses have what aspect in common with each other? a. They are physical barriers against invading pathogens. b. They recognize specific pathogens. c. They involve the production of antibodies. d. They involve unique cells that attack invading pathogens.
a.
How do superantigens enable pathogens to hide from the immune system if they actually stimulate the immune system? a. They cause the immune system to produce an exaggerated response, distracting it from the actual pathogen. b. They cause the immune system to destroy IgA antibodies. c. They cause the immune system to turn on itself. d. They cause fever, which destroys the complement proteins.
c
How does a capsule help certain bacteria evade detection by the immune system? a. Capsules have the ability to destroy antibodies secreted by the immune system. b. Capsules allow the bacteria to stick together, creating a larger mass that is too big for immune cells to engulf. c. The capsule is composed of polysaccharides that are similar to those found in the host; thus, the immune system does not recognize it as foreign. d. The capsule makes the bacterium too sticky to be phagocytosed by the immune cells.
a
If a new bacterial pathogen entered a human body through an accidental needle stick, the first cell that would try to kill the pathogen would likely be a. a phagocyte. b. an antibody-producing cell. c. a cytotoxic T cell.
a
Influenza virus targets a. respiratory epithelium. b. throat epithelium. c. oral cavity cells. d. gastrointestinal cells.
b
Endotoxins are also known as a. interleukin-1. b. Lipid A. c. prostaglandins. d. cytokines.
b
The process by which microorganisms cause diseases is known as a. infection. b. pathogenesis. c. LD50 (lethal dose50). d. virulence.
a.
A chemical that denatures proteins is MOST likely to be classified as a(n) ________ agent. a. Bacteriodical b. Bacteriostatic c. Detergent d. Antiseptic
c
A patient admitted to the hospital with muscle weakness and paralysis is put on a ventilator because of breathing difficulties. It is determined that the symptoms are the result of a bacterial exotoxin. Which of the following is the most likely source of this toxin? a. contaminated water b. a puncture wound c. canned food d. airborne bacteria
a.
A pharmaceutical company that uses the Limulus amoebocyte lysate (LAL) assay to test water that is used to make sterile saline for intravenous administration is trying to detect small amounts of which of the following? a. endotoxin b. Vibrio cholerae c. amoebae d. E. coli
a
A researcher wanted to determine the LD50 (lethal dose50) for a newly-isolated bacterial pathogen. Mice were inoculated with diluted cultures containing between 101 and 107 cells. After two days, all of the mice had died, EXCEPT for the uninoculated controls. Which of the following is the most likely explanation? a. This pathogen is highly virulent in mice. b. The pathogen has become attenuated. c. The pathogen has a very high LD50 d. Mice are not good model animals for this pathogen.
d
A response that is uniquely directed against pathogenic Bordetella pertussis would involve what component? a. Inflammation b. Skin barrier c. The complement system d. Antibodies
b.
All of the following areas of the human body should be microbially sterile EXCEPT __________. a. the lymphatic system b. the respiratory tract c. a fetus in utero d. the bloodstream
a.
An antiseptic (or germicide) is distinguished from other sterilizing compounds by a. Being able to be used on living tissues without harm b. Its ability to protect from subsequent microbial infections- not just initial sterilization c. Killing all bacteria and microscopic fungi but not being effective against viruses d. Being able to inhibit growth of microorganisms but not necessarily kill all of them
e
An exotoxin that has the ability to kill or damage host cells is referred to as a(n) a. A-B toxin. b. superantigen. c. enterotoxin. d. neurotoxin. e. cytotoxin.
c.
B cells interact directly with a. inflammation. b. the complement system. c. helper T cells. d. phagocytes.
d
Both the innate and adaptive defenses of the immune system work to prevent a. penetration by invading pathogens. b. disease. c. colonization by pathogens. d. all of the above
a
Extensive growth of the streptococci in a thick bacterial layer on acidic glycoproteins on the teeth is called a. dental plaque. b. periodontitis. c. dental caries. d. dental biofilm.
b
Karen stepped on a rusty nail while walking her dog barefoot. She needs to be treated to prevent damage by which exotoxin? a. botulinum exotoxin b. tetanus exotoxin c. hemolysin d. cholera exotoxin
a
Meningitis and gonorrhea are caused by a. Neisseria species. b. measles virus. c. Pseudomonas species.
c
Normal flora ________ colonization of pathogenic organisms. a. promote b. accelerate c. prevent d. maintain
b.
Organisms that colonize skin __________. a. are always aerobes b. are mostly gram-positive bacteria c. do not include eukaryotes d. are never pathogenic
a
Staphylococcus aureus produces ________, leading to fibrin clots that protect them from attack by host cells. a. coagulase b. amylase c. collagenase d. lipase
d.
The MOST effective antibiotics in preventing growth of disease-causing bacteria are a. Bacteriostatic b. Bacteriolytic c. Bacteriodical d. b and c
C
The ability to cause disease is __________. a. colonization b. virulence c. pathogenicity d. infection
b
The collective term for the organisms living on or in the human body is: a. transient microbial flora. b. normal microbial flora. c. fomite flora. d. pathogenic flora.
d
The decrease or loss of virulence of a pathogen is referred to as a. aging. b. disinfectivity. c. lethal dose. d. attenuation.
b
The dose of an antigen that kills 50% of animals in a test group and is used to estimate the virulence of a pathogen is known as a. Virulence-50. b. LD50 (lethal dose50). c. Death rate-50. d. Antigen dose50.
a
The exotoxin that functions by destroying cell membranes is called __________. a. a cytolytic toxin b. an enterotoxin c. an A-B toxin d. a superantigen toxin
b.
The following compounds are all produced by intestinal microflora EXCEPT a. vitamin B12. b. vitamin C. c. flatus. d. vitamin K.
c
The human gastrointestinal tract includes all of the following EXCEPT the a. large intestine. b. small intestine. c. epiglottis. d. stomach.
a.
Your laboratory supervisor has given you a plastic petri dish filled with soil to sterilize using radiation. What type of radiation will you use? a. Ionizing radiation b. Microwave radiation c. UV radiation d. Solar radiation
b.
________ are toxic proteins released from the pathogen as it grows. a. Microtoxins b. Exotoxins c. Endotoxins d. Macrotoxins
d.
________ in saliva cleaves glycosidic linkages in peptidoglycan present in bacterial cell walls, weakening the wall and causing cell lysis. a. Lipid A b. Fibrin c. Mucus d. Lysozyme
