Which of the following is an organ of the gastrointestinal tract?
C) the esophagus
Where in the digestive tract does the absorption of water take place?
A) the large intestine
Which of the following is a fungus which commonly lives in the large intestine?
Streptococcus mutans is associated with
D) dental caries
Porphyromonas gingivalis is associated with
Which of the following is now known to be the cause of most peptic ulcers?
C) Helicobacter pylori
Urease is an important virulence factor of which of the following?
B) Helicobacter pylori
The most important virulent factor of Vibrio cholerae is
A) its ability to produce a potent exotoxin
The major symptoms of cholera are attributable to which of the following?
D) activation of adenylate cyclase
Which of the following serotypes of Salmonella enterica causes most cases of human salmonellosis in the United States?
E) both Enteritidis and Typhimurium
Which of the following is a defining characteristic of coliforms?
C) They ferment lactose
Escherichia. coli O157:H7 is primarily associated with which of the following foods?
E) ground beef
The most common cause of traveler's diarrhea is
A) Escherichia coli
Shigellosis can be differentiated from salmonellosis by the fact that Shigella
C) multiplies in the host cell's cytosol
The most common bacterial cause of diarrhea that sends people to doctors in the United States is
A young woman being treated for serious burns develops severe diarrhea accompanied by intense abdominal pain. She passes several watery, foul-smelling, bloody stools a day. A colonoscopy reveals patches of yellowish lesions in the large intestine. The probably causative agent is
C) Clostridium difficile
The common source of contamination in the majority of cases of staphylococcal food poisoning (intoxication) is
C) the skin of food preparers
Which of the following statements is TRUE with regard to oral herpes?
D) Lesions can be triggered by emotional stress or physiologic changes.
Which of the following is the major sign or symptom of mumps?
The viruses responsible fo the majority of infant deaths resulting from diarrhea in the world are the
Which of the following hepatitis viruses usually produces subclinical infections?
The intracellular parasite usually acquired in contaminated drinking water which causes a persistent watery diarrhea is
E) Cryptosporidium parvum
Which of the following conditions usually results in severe acute liver damage?
E) co-infection with hepatitis B and hepatitis delta viruses
A vaccine is available against which of the following?
D) both hepatisis A and hepatitis B
Of the following, who is most likely to develop a chronic infection with hepatitis B virus?
A man reports to his doctor that he is tired all the time and his urine has become darker in color. He has not experienced fever or vomiting recently. The physician notes that his eyes are yellowing and his abdomen is swollen. The man has a history of kidney transplant and recently returned from an overseas trip. The man may be infected with
C) hepatitis E virus
Diagnosis of hepatitis B infection is made by the observation of which of the following in the patient's body fluids?
A) Dane particles
Which of the following is a notable symptom of giardiasis?
B) foul-smelling "rotten egg" stools
Which of the following causes "beaver fever?"
B) Giardia intestinalis
Which of the following statements is TRUE with regard to Entamoeba histolytica?
B) it causes pseudopodia to attach to the intestinal lining
Where in a tapeworm would you expect to find fertilized eggs?
A) at the end of the strobila
Tapeworms are usually transmitted to humans through ingestion of
Differentiation between Taenia saginata and Taenia solium is carried out via examination of the
Which of the following is a common childhood parasite in the United States?
E) Enterobius vermicularis
What is the primary symptom of Enterobius infections?
D) perianal itching
A large number of people in a community experience diarrhea with fever. Public health authorities investigate and find that the people are passing dark urine, and some have yellowish skin. Furthermore, all of the affected individuals recently ate at a new restaurant in town known for its wide variety of fresh imported vegetables. Which of the following is the most likely causative agent?
C) hepatitis A virus
The DNA virus known as "serum hepatitis" is
Peritonitis may develop in severe cases of
What member of the human intestinal microbiota occasionally causes life-threatening disease?
C) Clostridium difficile
Accessory organ infections are caused by
A) mumps virus
Cholera toxin is composed of five A subunits and one B subunit
Salmonella is part of the normal microbiota of virtually all vertebrates except humans.
Cholera toxin is composed of five A subunits and one B subunit.
All tapeworms are intestinal parasites that completely lack digestive systems
omplete recovery from hepatitis A infection occurs 99% of the time.
Vomiting is a common sign of viral gastroenteritis.
Peptic ulcers are erosions of the lining of the small or large intestines.
Dysentery is a severe type of gastroenteritis in which stools contain mucus and blood.
Supportive care is the only treatment for staphylococcal food poisoning.
Contamination of meat with tapeworm cysts can be detected by visual inspection.