Chapter 24 digestive system microbio mcgraw hill

In which of these organs does a carrier of typhoid bacilli maintain the bacteria? A) Liver B) Gallbladder C) Peyer's patches D) Colon E) Liver AND Peyer's patches

B

The diarrhea of cholera has been described as A) a viscous fluid. B) a rice water stool. C) small in volume. D) somewhat watery. E) dysentery.

B

The symptoms of cholera are due to the action of A) an endotoxin. B) an exotoxin. C) modified mucus. D) flagella. E) an exotoxin AND an endotoxin

B

Which of the following E. coli serovars give rise to a disease similar to that caused by Shigella sp.? A) Enterotoxigenic B) Enteroinvasive C) Enteropathogenic D) Enterohemorrhagic E) All of the choices are correct.

B

A common source of cholera infection is A) acid rain. B) unpasteurized milk. C) fecal contaminated water. D) boiled water. E) acid rain AND boiled water.

C

Which of the following type of hepatitis is/are associated with liver cancer or cirrhosis? A) Hepatitis A B) Hepatitis B C) Hepatitis C D) Hepatitis B AND hepatitis C E) Hepatitis A AND hepatitis B

D

Cryptosporidium parvum may infect A) dogs. B) pigs. C) cattle. D) humans. E) All of the choices are correct.

E

Entamoeba histolytica A) causes amebiasis. B) may form cysts. C) cysts survive passage through the stomach. D) may produce a cytotoxic enzyme. E) All of the choices are correct.

E

Giardiasis may be contracted from A) another person. B) clear mountain streams. C) chlorinated city water. D) cold filtered beer. E) another person, clear mountain streams, AND chlorinated city water.

E

Helicobacter pylori appears to have some connection with A) acid reflux disease. B) ulcers. C) dental caries. D) stomach cancer. E) ulcers AND stomach cancer.

E

Helicobacter pylori is able to survive in the stomach by its ability to produce A) lactic acid from sugar. B) ammonia from urease. C) fatty acids from sebum. D) neutralizing proteins from glucans. E) ammonia from urea.

E

Most bacterial intestinal infections may be traced to all of the following EXCEPT A) Vibrio species. B) C. jejuni. C) Salmonella species. D) Enterobacteriaceae. E) Haemophilus species.

E

Mumps is a good candidate for elimination from the population due to A) the existence of an effective vaccine. B) a human-only reservoir. C) the absence of a latent state. D) a single serotype. E) All of the choices are correct.

E

The animal(s) often associated with Salmonella strains is/are A) turtles. B) iguanas. C) baby chickens. D) ducks. E) All of the choices are correct

E

The toxins involved in intestinal infections typically A) kill cells by inhibiting DNA synthesis AND modify cell physiology resulting in increased secretion of water and electrolytes. B) modify cell physiology resulting in increased secretion of water and electrolytes. C) modify cell physiology resulting in decreased secretion of water and electrolytes. D) kill cells by inhibiting DNA synthesis AND modify cell physiology resulting in decreased secretion of water and electrolytes. E) kill cells by inhibiting protein synthesis AND modify cell physiology resulting in increased secretion of water and electrolytes

E

What are possible complications of mumps? A) Orchitis and infertility B) Meningitis C) Miscarriage D) Sudden onset deafness E) All of the answer choices are correct.

E

Which of the following antigens are useful markers for hepatitis B infection? A) HBsAg B) HBcAg C) HBcAg AND HBsAg D) HBeAg E) HBcAg, HBsAg, AND HBeAg

E

T/F: Cyclosporiosis is transmissable from person to person.

False

T/F: The infectious dose for cholera is much larger than that for shigellosis.

False

T/F: Both Giardia lamblia and Cryptosporidium parvum are resistant to chlorine.

True

T/F: Cyclospora cayetanensis has, so far, not been identified with an animal source.

True

T/F: Helicobacter pylori appears connected to stomach cancer and ulcers.

True

T/F: The mumps virus initially infects the respiratory tract.

True

Shigella and cholera toxin both A) have an A-B arrangement. B) work through ADP ribosylation. C) increase cAMP levels. D) prevent protein synthesis. E) are endotoxins.

A

You suspect that your brother has giardiasis, caused by Giardia lamblia. Which of the following is NOT True about this disease? A) The cysts of G. lamblia are are resistant to stomach acid and are infectious. B) A person with giardiasis diarrhea is likely to eliminate G. lamblia cysts rather than trophozoites. C) The causative organism has energy-metabolizing organelles called mitosomes. D) Giardiasis is a zoonotic disease. E) Chlorinated water may still contain G. lamblia because the cysts are resistant to this chemical.

A

Your patient asks what treatment she will be given for the CDI. You explain that initially, she will be taken off all antibiotics. This may cure her by A) allowing her own gut normal microbiota to recover and to outcompete the C. difficile. B) strengthening her innate and adaptive immune responses against the Clostridium difficile. C) destroying any endospores that the C. difficile may have produced. D) destroying any endospores that the C. difficile may have produced AND strengthening her innate and adaptive immune responses against the Clostridium difficile. E) increasing antibiotic sensitivity in the Clostridium difficile, thereby weakening the pathogen so that the person's own immune system gets effectively rid of it.

A

Clostridium difficile produces toxins that are involved in the pathogenesis of CDI. Which toxins are associated with ALL strains of this organism? A) Toxin A and toxin B B) CagA and vacA C) CagA and toxin A D) Binary toxin and VacA E) Toxin A, toxin B, and binary toxin

A

The most commonly identified waterborne illness in the United States is A) giardiasis. B) amoebiasis. C) cryptosporidiosis. D) balantidiasis. E) histoplasmosis.

A

The signs and symptoms of giardiasis vary among people. Which of the following is your brother unlikely to experience with his infection? A) Bloody, frothy urine B) Jaundice and malabsorption C) Indigestion and gas D) Nausea and vomiting E) These all may be experienced with giardiasis.

A

Which of the following media would you use to cultivate Vibrio cholerae? A) Selective-containing NaCl and with basic pH. B) Differential-containing NaCl and with basic pH. C) Selective-containing HCl and with acidic pH. D) Differential-containing HCl and with acidic pH. E) V. cholerae cannot be cultured in the laboratory.

A

Which of these bacteria require a special medium and microaerophilic conditions? A) Campylobacter jejuni B) Escherichia coli C) Pseudomonas aeruginosa D) Staphylococcus aureus E) Salmonella enterica

A

Why might it be more difficult to prepare a vaccine against noroviruses than against rotaviruses? A) We haven't been able to culture noroviruses in a lab setting yet. Without a starting culture, we can't create a vaccine. B) Noroviruses are RNA viruses, where rotaviruses are DNA viruses. RNA viruses mutate far more easily than DNA viruses, so we COULD make a vaccine, but it would be rendered useless fairly quickly as the virus mutates. C) We lack a proper culturing method for large-scale production of target cells for norovirus, whereas we have such a system for the target cells of rotaviruses. Without a system to get large numbers of target cells, we can't produce a vaccine. D) Norovirus is much more infectious than rotavirus. As such, it's much harder to work with safety. This makes production of a vaccine too dangerous and unpredictable. E) This question is misleading. It has been relatively simple to create vaccines against both of these virus types.

A

You tell your patient that her CDI is caused by a bacterium belonging to the genus Clostridium. Which of the following is True of all Clostridia? A) They are Gram-positive, rod-shaped, endospore-forming obligate anaerobes. B) They are encapsulated, flagellated, toxin-producing aerobes. C) They are Gram-negative, rod-shaped, endospore-forming obligate aerobes. D) They are flagellated and always cause significant inflammation. E) Clostridial infections only occur if a state of dysbiosis exists in the host.

A

Your patient wonders how she contracted CDI. Which of the following would be a good explanation for her? A) She is elderly; elderly people frequently develop gastrointestinal complaints such as CDI. It is to be expected in an aging person. B) She has been on antibiotic therapy because of her surgery. The antibiotics disrupted her normal intestinal microbiota, allowing any C. difficile present to flourish. C) C. difficile is usually a community-acquired organism. She most likely came to the hospital already infected with it but it takes several days for signs and symptoms of CDI to appear. D) Most surgical equipment is contaminated with C. difficile endospores, which are ubiquitous. Most likely your patient acquired CDI directly from her surgery. E) Nobody knows how people contract CDI. The causative bacterium is a common environmental organism and it is not known how it becomes pathogenic.

A

A mysterious sequel to Campylobacter jejuni infections is A) Reye's syndrome. B) Guillain-Barré syndrome. C) Tourette's syndrome. D) Pasteur's syndrome. E) Campylobacter syndrome.

B

Amebiasis A) is caused by Cryptosporidium parvum. B) often causes a bloody diarrhea. C) is an infection of the stomach. D) is restricted to temperate climates. E) is caused by Cryptosporidium parvum AND often causes a bloody diarrhea.

B

Please select the INCORRECT statement regarding mumps and oral herpes. A) Herpes simplex virus is an enveloped double-stranded DNA virus while mumps virus is an enveloped single-stranded RNA virus. B) Both herpes simplex virus and mumps virus are extremely resistant to detergents and disinfectants. C) Cells infected with HSV exhibit an intranuclear inclusion body; cells infected with mumps virus do not exhibit this body. D) Herpes simplex virus and mumps virus are both transmitted in the saliva of infected people. E) A person with HSV infection may experience recurrences while a person who has recovered from mumps has lifelong immunity

B

Shigella moves from cell to cell using A) cilia. B) actin tails. C) pili. D) flagella. E) flagella AND pili.

B

The food products most commonly contaminated with Salmonella strains are A) meat and seafood. B) eggs and poultry. C) milk and cheese. D) fruit and vegetables. E) eggs and fruit.

B

The initial attachment required for establishment of an intestinal infection is by A) flagella. B) pili. C) cilia. D) pseudopodia. E) a capsule.

B

The most common chronic blood-borne infection in the U.S. is A) hepatitis D. B) hepatitis C. C) hepatitis B. D) hepatitis A. E) none of these.

B

The most common infectious disease of humans is A) the common cold B) dental caries C) hepatitis A D) halitosis E) influenza

B

The oocytes of Cyclospora cayetanensis A) are mature when eliminated in the stool. B) do not contain sporozoites when passed in the feces. C) are smaller than the oocytes of Cryptosporidium parvum. D) give rise to three sporozoites. E) contain sporozoites when passed in the feces.

B

The viral disease that characteristically infects the parotid glands is A) measles. B) mumps. C) herpes. D) chickenpox. E) varicella.

B

Vibrio cholerae and most salmonellae are A) killed by acid conditions. B) stimulated by acid conditions. C) killed by low concentrations of salt. D) killed by neutral conditions. E) acidophiles

B

Where in the body does the latent, non-infectious, non-replicating form of the herpes simplex virus persist? A) Motor neurons B) Sensory nerves C) Red blood cells D) Cranial nerves E) Spinal cord

B

Who determined that the cholera outbreak in 1850s London was due to contaminated water and approached the problem by removing the pump handle at the contaminated site? A) Pasteur B) Snow C) Koch D) Smith E) Semmelweis

B

Cholera is the classic example of a(n) A) foodborne illness. B) zoonosis. C) very severe form of diarrhea. D) opportunistic infection. E) vector-borne disease.

C

How does H. pylori survive the acidic conditions of the stomach? A) Producing urease, an enzyme that converts urea to ammonia, thereby creating an alkaline microenvironment. B) Burrowing within the layer of mucus that coats the stomach lining. C) Producing urease, an enzyme that converts ammonia to urea, thereby creating an alkaline microenvironment. D) Producing urease, an enzyme that converts urea to ammonia, thereby creating an alkaline microenvironment AND burrowing within the stomach mucus layer. E) Producing urease, an enzyme that converts ammonia to urea, thereby creating an alkaline microenvironment AND covering its flagella with protective sheaths.

D

Intestinal protozoan infections are typically spread by A) the respiratory route. B) blood transfusion. C) body fluids. D) the fecal-oral route. E) vectors.

D

Most cases of Salmonella gastroenteritis have a(n) A) water source. B) human source. C) plant source. D) animal source. E) human source AND animal source.

D

Please select the definition regarding aspects of the digestive system that is INCORRECT. A) Cariogenic-causing dental caries. B) Dysentery-diarrhea characterized by fecal pus and blood. C) Cirrhosis-liver scarring that interferes with function. D) Gingivitis-inflammation of the teeth and gums. E) Dysbiosis-imbalance of the intestinal normal microbiota.

D

The passage from the mouth to the anus is termed the A) gut canal B) oral cavity C) grand canal D) gastrointestinal tract E) peristalsis

D

The primary treatment for cholera is A) the administration of antibiotics. B) vaccination AND the administration of antibiotics. C) by blood transfusion AND simple rehydration. D) simply rehydration. E) vaccination AND by blood transfusion.

D

There are several stages in the life cycle of G. lamblia. Which is the correct sequence? 1) Trophozoites multiply in the intestine. 2) Mature cysts or trophozoites are released in feces. 3) Cysts pass through the stomach to the lower small intestine. 4) Dehydration in the large intestine stimulates formation of cysts. 5) Cysts enter the mouth by ingestion of contaminated food or water. 6) Trophozoites are released from the cysts. A) 1, 2, 3, 4, 5, 6 B) 2, 3, 1, 5, 4, 6 C) 5, 2, 3, 1, 6, 4 D) 5, 3, 6, 1, 4, 2 E) 2, 5, 6, 1, 3, 4

D

Which of the following E. coli serovars produces a toxin somewhat similar to that produced by Shigella dysenteriae? A) Enterotoxigenic B) Enteroinvasive C) Enteropathogenic D) Enterohemorrhagic E) All of the choices are correct

D

Which of the following hepatitis viruses are transmitted by the fecal-oral route? A) HAV and HBV B) HAV and HCV C) HAV, HBV, and HCV D) HAV and HEV E) All hepatitis viruses

D

Which of the following is specific to H. pylori strains associated with stomach cancer? A) They are microaerophilic. B) They have sheathed flagella. C) The are acidophilic. D) They produce CagA. E) They produce VacA

D

You brother asks whether he will be given penicillin for his infection. What do you tell him? A) Yes-G. lamblia has a peptidoglycan cell wall. B) Yes-G. lamblia has 70S ribosomes. C) No-G. lamblia is a virus. D) No-G. lamblia is a protozoan. E) No-G. lamblia has a protective LPS layer.

D

Which of the following gastrointestinal pathogens produce A-B toxins? A) Vibrio cholerae B) Some strains of Shigella dysenteriae C) Helicobacter pylori AND some strains of Shigella dysenteriae D) Helicobacter pylori AND Vibrio cholerae E) Vibrio cholerae AND some strains of Shigella dysenteriae

E

Which of the following groups contain diarrhea-causing E. coli? A) Enterotoxigenic B) Enteroinvasive C) Enteropathogenic D) Enterohemorrhagic E) All of the choices are correct

E

Which of the following is not a typical sign or symptom of H. pylori gastritis? A) Belching B) Bloating C) Vomiting D) Pain E) Fever

E

T/F: The saliva of asymptomatic carriers of herpes simplex is not infectious.

True

T/F: Virulent strains of Shigella typically carry an R plasmid.

True

A painful finger infection attributable to herpes virus is known as a(n) A) finger sore. B) abrasion lesion. C) furuncle. D) herpetic whitlow. E) nurse's lesion.

D

Hepatitis A spreads via A) the respiratory route. B) blood transfusion. C) body fluids. D) the fecal-oral route. E) the fecal route.

D

Explain how Vibrio cholerae causes cholera without apparent damage to the intestinal epithelium. A) This microbe causes destruction of the cellular structures underneath the intestinal epithelium-this is what induces the watery rice-stool characteristic of the illness. This leaves the overlying intestinal epithelium intact. B) This microbe directly invades the intestinal epithelial cells, but does not kill them. Instead, while multiplying inside them, it causes them to secrete large amounts of chloride ions. This induces water to follow by osmosis, resulting in the watery rice-stool characteristic of the illness. C) This microbe attaches to the surface of intestinal epithelial cells, producing an exotoxin that causes the epithelium to secrete chloride ions. This induces large amounts of water to follow by osmosis, resulting in the watery rice-stool characteristic of the illness. D) The inflammatory reaction to the presence of this microbe causes the watery rice-stool characteristic of the illness. Therefore, it's technically the immune response that initiates the disease, although this response is induced by the presence of the microbe on the intestinal epithelium. E) This microbe attaches to the surface of intestinal epithelial cells, producing an endotoxin that causes the epithelium to secrete potassium ions. This induces small amounts of water to follow by osmosis, resulting in the watery rice-stool characteristic of the illness.

C

Most North American outbreaks of Cyclospora cayetanensis have been associated with A) imported cattle. B) iguanas. C) imported vegetables. D) chickens. E) foreign mosquitoes.

C

Once H. pylori is in a host's stomach, what happens? A) The bacteria move away from the neutral mucus-secreting epithelium toward the acidic stomach lumen. B) H. pylori moves from the basic stomach lumen up toward the neutral esophagus. C) The bacteria move away from the acidic stomach lumen toward the neutral mucus-secreting epithelial layer. D) The bacteria move away from the acidic stomach lumen toward the neutral small intestine. E) H. pylori moves from the neutral small intestine toward the acidic stomach lumen.

C

The animal(s) frequently associated with Campylobacter jejuni is/are A) turtles. B) iguanas. C) chickens. D) dogs. E) All of the choices are correct.

C

The most notorious typhoid carrier was A) Typhoid Tilly. B) Typhoid Tom. C) Typhoid Mary. D) Typhoid Mark. E) Typhoid salmonella

C

Viral gastroenteritis in infants and children is most commonly caused by A) herpes. B) hepatitis B. C) rotavirus. D) norovirus. E) influenza virus.

C

Viral gastroenteritis that affects people of all ages and usually lasts less than 3 days is caused by A) herpes. B) hepatitis B. C) norovirus. D) rotavirus. E) influenza virus.

C

What are A/E lesions, produced by some strains of E. coli? A) Inflammatory patches caused by the attachment of the bacteria to the intestinal lining by small suction appendages. B) Intestinal abscesses that form after the bacteria have entered M cells, destroying them and causing bloody diarrhea. C) Intestinal damage characterized by pedestals that form under bacterial cells as a result of induced actin rearrangement in the intestinal cell. D) Cytoplasmic extensions induced in intestinal epithelial cells by the injection of superantigens via type III secretion systems. E) Appendages used by E. coli strains to avoid phagocytosis and enter M cells of the intestinal epithelium.

C

What type of vaccine protects against mumps virus? A) Toxoid B) Conjugate C) Attenuated D) Subunit E) Inactivated whole agent

C

Which of the following has shown some effectiveness in treating a herpes infection? A) AZT B) Protease inhibitors C) Acyclovir D) Cephalosporin E) Broad spectrum antibiotics

C

Which of the following is NOT a mechanism of spread of HBV? A) Blood B) Blood products C) Saliva D) Semen E) These are all mechanisms of spread for HBV.

C

Which statement regarding CagA and VacA of H. pylori is INCORRECT? A) Strains of H. pylori that produce CagA are associated with stomach cancer. B) CagA is delivered into host cells by a secretion system. C) VacA is an A-B toxin that increases urea flow into the stomach. D) VacA interferes with the function of T cells. E) CagA interferes with cell signaling and promotes inflammation.

C

Why don't medications such as acyclovir cure oral herpes simplex infections? A) Acyclovir is an antiviral medication, but oral herpes is caused by a bacterium. B) Acyclovir is an antibacterial medication, but oral herpes is caused by a virus. C) Herpes simplex virus DNA persists in a latent form that is not removed by acyclovir. D) Herpes simplex virus RNA persists in a latent form that is not removed by acyclovir. E) Herpes simplex virus forms endospores that are resistant to all medications.

C

Would you expect an individual with giardiasis who has diarrhea to be more likely to transmit the disease than an individual with giardiasis who does NOT have diarrhea? Why or why not? A) No. This illness is spread by respiratory droplets, so diarrhea as a symptom shouldn't matter for transmission of the disease. B) No. This illness is spread by sexual contact, so diarrhea as a symptom shouldn't matter for transmission of the disease. C) Yes. This illness is spread by the fecal-oral route, so presence of diarrhea as a symptom should dramatically increase the possibility of transmission of infection. D) Yes. This illness is spread by insects that feed on contaminated fecal matter, becoming infected themselves. The disease is spread to new individuals when these infected insects bite a susceptible person, transmitting the cysts of the protozoan. As such, diarrhea as a symptom would increase the risk of transmission through biting insects to new individuals. E) No. This illness is spread when people ingest cysts, and a person with severe diarrhea excretes primarily trophozoites; an asymptomatic person is more likely to excrete cysts and is therefore more infectious.

C