Microbiology Chapter 25

Which of the following is directly involved in the initiation of dental caries?
A) sucrose
B) lysozyme
C) lactic acid
D) crevicular fluid
E) dentin

lactic acid

Clostridium difficile-associated diarrhea is usually preceded by
A) eating contaminated food.
B) a blood transfusion.
C) extended use of antibiotics.
D) improper food storage.
E) travel to an underdeveloped country

extended use of antibiotics

Which of the following statements about salmonellosis is FALSE?
A) It is a bacterial infection.
B) Severity of disease depends on number of organisms ingested.
C) A healthy carrier state exists.
D) The mortality rate is high.
E) It is often associated with poultry products

the mortality rate is high

Disease-causing exotoxins are produced by all of the following organisms EXCEPT
A) Clostridium perfringens.
B) Vibrio cholerae.
C) Shigella dysenteriae.
D) Staphylococcus aureus.
E) Clostridium botulinum

shigella dysenteriae

Which one of the following diseases of the gastrointestinal system is transmitted by the respiratory route?
A) staphylococcal enterotoxicosis
B) mumps
C) Vibrio gastroenteritis
D) bacillary dysentery
E) traveler’s diarrhea

mumps

The digestive tract is essentially one long tube. The order of the structures, beginning with the mouth, is
A) pharynx, esophagus, stomach, small intestine, large intestine.
B) esophagus, pharynx, stomach, small intestine, large intestine.
C) pharynx, esophagus, stomach, large intestine, small intestine.
D) esophagus, stomach, pharynx, small intestine, large intestine.
E) pharynx, stomach, esophagus, small intestine, large intestine

pharynx, esophagus, stomach, small intestine, large intestine

Which of the following helminthic diseases is a common infestation found in the southeastern United States?
A) Enterobius vermicularis
B) Ascaris lumbricoides
C) Taenia saginata
D) Trichuris trichiura
E) Echinococcus granulosus

Ascaris lumbricoides

Poultry products are a likely source of infection by
A) Helicobacter pylori.
B) Salmonella enterica.
C) Vibrio cholerae.
D) Shigella spp.
E) Clostridium perfringens

Salmonella enterica

All of the following infections can result from drinking contaminated water EXCEPT
A) Cyclospora infection.
B) giardiasis.
C) trichinellosis.
D) cholera.
E) cryptosporidiosis

trichinellosis

Which of the following organisms feeds on red blood cells?
A) Giardia lamblia
B) Escherichia coli
C) Taenia spp.
D) Vibrio parahaemolyticus
E) Entamoeba histolytica

Entamoeba histolytica

In humans, beef tapeworm infestations are acquired by ingesting
A) the eggs of Taenia saginata.
B) segments of Taenia solium tapeworms.
C) water contaminated with Diphyllobothrium latum eggs.
D) cysticerci of Taenia saginata in undercooked meat.
E) cysticerci of Taenia solium in undercooked meat

cysticerci of Taenia saginata in undercooked meat

Which of the following statements about staphylococcal food poisoning is FALSE?
A) It is caused by ingesting an enterotoxin.
B) It can be prevented by adequate refrigeration of food.
C) It can be prevented by heating foods to 50°C for 15 minutes.
D) It is treated by replacing water and electrolytes.
E) It is characterized by rapid onset and short duration of symptoms.

it can be prevented by heading foods to 50 degrees C for 15 minutes

The most common cause of traveler’s diarrhea is
A) Shigella spp.
B) Salmonella enterica.
C) Giardia lamblia.
D) Escherichia coli.
E) Campylobacter jejuni

Escherichia coli

Acute gastroenteritis that occurs after an incubation period of two to three days and commonly affects children is probably caused by
A) Giardia.
B) rotavirus.
C) Salmonella.
D) Staphylococcus aureus.
E) Trichinella

rotavirus

Which of the following is mismatched?
A) hydatid disease — humans are the definitive host
B) Taenia infestation — humans are the definitive host
C) trichinellosis — humans eat larva of parasite
D) pinworm infestation — humans ingest parasite’s eggs
E) hookworm infestation — parasite bores through skin

hydatid disease – humans are the definitive host

Thorough cooking of food will prevent all of the following EXCEPT
A) trichinellosis.
B) beef tapeworm.
C) staphylococcal food poisoning.
D) salmonellosis.
E) shigellosis.

staphylococcal food poisoning

Most of the normal microbiota of the digestive system are found in the
A) mouth.
B) stomach.
C) stomach and small intestine.
D) small intestine and large intestine.
E) accessory structures

small intestine and large intestine

Gums bleeding while brushing one’s teeth is most commonly associated with
A) halitosis.
B) cavities.
C) gingivitis.
D) periodontitis.
E) trench mouth

gingivitis

Typhoid fever differs from salmonellosis in that in typhoid fever
A) the microorganisms multiply within macrophages.
B) the incubation period is much longer.
C) the symptoms are due to infection of the gallbladder.
D) infection is spread only in the feces of domesticated animals.
E) infection occurs due to ingestion of endospores

the incubation period is much longer

Which of the following organisms is likely to be transmitted via contaminated shrimp?
A) Trichinella spiralis
B) Vibrio parahaemolyticus
C) Giardia lamblia
D) Clostridium perfringens
E) Staphylococcus aureus

vibro parahaemolyticus

Which of the following organisms is likely to be transmitted via undercooked pork and horse?
A) Salmonella enterica
B) Staphylococcus aureus
C) Trichinella spiralis
D) Entamoeba histolytica
E) Shigella spp

Trichinella spiralis

A vaccine to provide active immunity to HBV is prepared from
A) viruses grown in tissue culture.
B) genetically modified yeast.
C) pooled gamma globulin.
D) viruses grown in embryonated eggs.
E) viral particles in patients

genetically modified yeast

Aflatoxin is a(n) ________ associated with ingestion of contaminated ________.
A) mycotoxin; peanuts
B) mycotoxin; rye or other cereal grains
C) enterotoxin; peanuts
D) enterotoxin; rye or other cereal grains
E) endotoxin; peanuts

mycotoxin; peanuts

Which of the following causes inflammation of the liver?
A) Salmonella enterica
B) Shigella spp.
C) hepatitis A virus
D) Vibrio cholerae
E) Escherichia coli

hepatitis A virus

"Rice water stools" are characteristic of
A) salmonellosis.
B) cholera.
C) bacillary dysentery.
D) amebic dysentery.
E) tapeworm infestation

cholera

Epidemics related to bacterial infection of the digestive system are typically caused by
A) biological vectors.
B) contaminated food and water.
C) unpasteurized milk.
D) the respiratory route.
E) exposure to contaminated soil

contaminated food and water

Many bacterial infections of the lower digestive tract are treated with
A) antitoxin.
B) penicillin.
C) water and electrolytes.
D) quinacrine.
E) thorough cooking

water and electrolytes

Dental plaque is an example of
A) a pellicle.
B) a biofilm.
C) gingivitis.
D) dentin.
E) tooth enamel

a biofilm

Which of the following is mismatched?
A) ergot — gangrene
B) Salmonella endotoxin — lyses red blood cells
C) Vibrio enterotoxin — secretion of Cl-, K+, and H2O
D) aflatoxin — liver cancer
E) shiga toxin — tissue destruction

Salmonella endotoxin – lyses red blood cells

Bacterial intoxications differ from bacterial infections of the digestive system in that intoxications
A) are transmitted via contaminated water.
B) are more severe.
C) have shorter incubation times.
D) are treated with antibiotics.
E) are accompanied by high fever

have shorter incubation times

The most common mode of HAV transmission is
A) contamination of food during preparation.
B) contamination of food before it reaches a food service establishment.
C) blood transfusion.
D) contaminated hypodermic needles.
E) airborne.

contamination of food during preperation

Which of the following correctly lists the stages of tooth decay?
A) plaque accumulation, destruction of enamel, advancement of decay through enamel, decay in dentin, decay in tooth pulp
B) decay in dentin, plaque accumulation, destruction of enamel, advancement of decay through enamel, decay in tooth pulp
C) plaque accumulation, destruction of enamel, decay in tooth pulp, advancement of decay through enamel, decay in dentin
D) destruction of enamel, advancement of decay through enamel, plaque accumulation, decay in dentin, decay in tooth pulp
E) destruction of enamel, plaque accumulation, advancement of decay through enamel, decay in dentin, decay in tooth pulp

plaque accumulation, destruction of enamel, advancement of decay through enamel, decay in dentin, decay in tooth pulp

A 38-year-old man had onset of fever, chills, nausea, and myalgia while vacationing on the Gulf of Mexico. On April 29, he had eaten raw oysters and gone wading in the warm coastal waters. On May 2, he was admitted to a hospital because of a fever of 39°C and two circular necrotic lesions on the left leg. He had a history of alcoholic liver disease. He was transferred to the ICU; therapy with antibiotics was initiated. On May 4, he died. Which of the following is the most likely cause?
A) Bacillus cereus
B) Cyclospora cayetanensis
C) Salmonella typhi
D) Vibrio vulnificus
E) hepatitis C virus

Vibrio vulnificus

Which of the following is included in GALT?
A) thymus
B) Peyer’s patches
C) tonsils
D) liver
E) salivary glands

Peyer’s patches

Microscopic examination of a patient’s fecal culture shows spiral bacteria. The bacteria probably belong to the genus
A) Campylobacter jejuni.
B) Escherichia coli.
C) Salmonella typhi.
D) Shigella spp.
E) Vibrio cholerae

Campylobacter jejuni

Which of the following pertains to typhoid fever?
A) It is acquired via ingestion of contaminated meat.
B) Enterotoxin spreads via the blood.
C) It is caused by several different species of Salmonella.
D) Causative microorganism multiplies in patient phagocytes.
E) It is also called bacillary dysentery

Causative microorganism multiples in patient phagocytes

All of the following are gram-negative rods that cause gastroenteritis EXCEPT
A) Clostridium perfringens.
B) Escherichia coli.
C) Salmonella typhi.
D) Shigella spp.
E) Yersinia enterocolitica

Clostridum perfingens

Helicobacter pylori can grow in the stomach because it
A) hides in macrophages.
B) makes a capsule.
C) possesses an enzyme that neutralizes HCl.
D) makes HCl.
E) invades epithelial cells

possesses an enzyme that neutralizes HCl

All of the following are eukaryotic organisms that cause diarrheal disease EXCEPT
A) Cryptosporidium.
B) Cyclospora.
C) Entamoeba.
D) Giardia.
E) Campylobacter

Campylobacter

All of the following pertain to pinworm infections EXCEPT
A) transmission is typically by contact with fomites or inhalation of eggs.
B) diagnosis is by detecting eggs on transparent tape pressed to the perianal area.
C) all family members living with the patient must also be treated.
D) it is most commonly transmitted by cysts in water.
E) it is a helminth disease

it is most commonly transmitted by cysts in water

What is a Dane particle?
A) the chlorine-resistant virus that causes HAV
B) the infectious virion that causes HBV
C) the spherical particles found in serum of patients with HBV
D) the filamentous particles that cause HAV
E) another name for an HBV surface antigen

the infectious virion that causes HBV

Which of the following is mismatched?
A) beef — E. coli O157:H7
B) custard and cream pies — Staphylococcus aureus
C) eggs — Trichinella spiralis
D) chicken — Campylobacter jejuni
E) oysters — Vibrio parahaemolyticus

eggs – trichinella spiralis

Following a county fair, 160 persons complained of gastrointestinal symptoms. Symptoms included diarrhea (84 percent), abdominal cramps (96 percent), nausea (84 percent), vomiting (82 percent), body aches (50 percent), fever (60 percent; median body temperature = 38.3°C); median duration of illness 6 days (range 10 hr to 13 days).

43) In Situation 25.1, fecal samples should be cultured for all of the following EXCEPT
A) Salmonella enterica.
B) Shigella spp.
C) Campylobacter jejuni.
D) enteropathogenic Escherichia coli.
E) Giardia lamblia

Giardia lamblia

Following a county fair, 160 persons complained of gastrointestinal symptoms. Symptoms included diarrhea (84 percent), abdominal cramps (96 percent), nausea (84 percent), vomiting (82 percent), body aches (50 percent), fever (60 percent; median body temperature = 38.3°C); median duration of illness 6 days (range 10 hr to 13 days).)

In Situation 25.1, fecal samples were found to be negative when cultured. The next step in diagnosing the cause of illness would be
A) to begin antibiotic therapy.
B) blood cultures.
C) microscopic examination of feces for oocysts.
D) microscopic examination of feces for viruses.
E) muscle biopsy.

microscopic examination of feces for oocysts

The relative risks shown in Table 25.1 were calculated for foods suspected of transmitting Salmonella. Which food is the most likely source of infection?
A) black beans
B) corn soup
C) jalapeño peppers
D) roma tomatoes
E) The answer cannot be determined based on the information provided

jalapeño peppers

Campylobacter gastroenteritis is the leading cause of foodborne illness in the United States.

true

Dental caries can also be referred to as periodontal disease.

false

Bacterial infections, but not intoxications, can cause diarrhea.

false

An outbreak of viral gastroenteritis occurs in a pediatrics ward. Rotavirus is the most likely causative agent.

true

Aflatoxin poisoning is associated with liver cancer.

true

Approximately 30 percent of the body’s immune system is located in the intestinal tract.

false

Lactic acid, an end product of fructose fermentation, causes breakdown of tooth enamel and, eventually, cavities.

true

Gastroenteritis due to ingestion of food contaminated with Staphylococcus aureus is due to intoxication by enterotoxins.

true

EHEC is a major cause of diarrhea in developing countries and may result in the death of small children.

false

H. pylori is able to survive the acidic environment of the stomach as a result of adaptations that allow it to increase the pH of the immediate environment.

true

Mary made her family’s favorite cream of broccoli soup for lunch. Lunch was forgotten when her son suddenly remembered he had a soccer game at noon. The family finally returned several hours later and sat down to eat. Although Mary reheated the soup (which had been left out at room temperature while they were gone), why is this no guarantee that Mary and her family will not become sick due to food poisoning?

…

Discuss why cholera epidemics are often associated with floods.

…

Compare the modes of transmission for hepatitis A, B, and C.

…

Describe the process of periodontal disease.

…

Multiple pathovars of E. coli are well characterized. Identify four different pathogenic strains and discuss the mechanism of disease for each.

…

Thinking of a mumps infection, how do the symptoms involve the GI tract, yet lead to airborne transmission of the disease? Why isn’t the disease transmitted by fecal-oral contamination instead?

…

Which of the following is NOT true for both hepatitis B and hepatitis C infection?

the disease is prevented by vaccination

What do hepatitis A and hepatitis B have in common?

both can be prevented by a vaccine

What organ is most affected by hepatitis B?

liver

Dental plaque is an example of

biofilm

Clostridium difficile- associated diarrhea is usually preceded by

extended use of antibiotics

Poultry products are a likely source of infection by

Salmonella eterica

Epidemics related to bacterial infection of the digestion system are typically casued by

contaminated food and water

Helicobacter pylori can grow in the stomach b/c it

possesses an enzyme that neutralized HCl

Most of the normal microbiota of the digestive system are found in the

Small intestine and large intestine

Which of the following is directly involved in the initiation of dental caries?

Lactic acid

Lactic acids, an end product of fructose fermentation, causes breakdown of tooth enamel and, eventually cavities

true

Gums bleeding while brushing one’s teeth is most commonly associated with

Gingivitis

Which of the following statements about salmonellosis is false?

the mortality rate is high

Which of the following statements about staphylococcal food poisoning is false?

it can be prevented by heating foods to 50 degrees C for 15 min

All of the following are gram (-) rods that cause gastroenteritis except

Clostridium perfingens

Campylobacter gastroenteritis is the leading cause of foodborne illness in the US

true

H. pylori is able to survive the acidic environment of the stomach as a result of adaptations that allow it to increase the pH of the immediate environment

true

Through cooking of food will prevent all of the following except

staphyloccoal food poisoning

Bacterial intoxications differ from bacterial infections of the digestive system in that intoxications

having shorter incubation times

Gastroenteritis due to ingestion of food contaminated with Staphylococcus aureus is due to intoxication by enterotoxins

true

"Rice water stools" are characteristics of

cholera

The most common cause of traveler’s diarrhea is

E. coli

The most common mode of HAV transmission is

contamination of food during preparation

A vaccine to provide active immunity to HBV is prepared from

genetically modified yeast

Vaccines can be used to protect at-risk individuals from all of the following liver diseases except

Hepatitis C

An outbreak of viral gastroenteritis occurs in a pediatrics ward. Rotavirus is the most likely causative agent

true

Acute gastroenteritis that occurs after an incubation period of two to three days and commonly affects children is probably caused by

Rotavirus