Micro Quiz 10

Vibrio cholerae primarily infects the: A. small intestine. B. rectum. C. stomach. D. large intestine

A

Hantavirus pulmonary syndrome is a viral respiratory disease caused by contact with: A. mosquitoes. B. rodents. C. bats. D. rat fleas.

B

Legionella pneumophila is generally transmitted by: A. contaminated drinking water. B. contaminated water in coolers, pools, and domestic water systems. C. contaminated food. D. personto-person contact.

B

Psychrotolerant microorganisms can survive and grow at: A. high salt or sugar concentrations. B. refrigeration temperatures. C. boiling temperatures. D. extreme fluctuations in water availability.

B

The Staphylococcus aureus toxins are: A. ectotoxins. B. superantigen toxins. C. neurotoxins. D. endotoxins.

B

The degree of susceptibility a food has to microbial activity is determined by its: A. water content. B. chemical characteristics, physical characteristics, and water content. C. chemical characteristics. D. physical characteristics.

B

The presence of specific ________ signals that a given water source might be contaminated with pathogens. A. exotoxins B. indicator microorganisms C. endotoxins D. chemical compounds

B

Verotoxin can cause: A. brain damage. B. hemorrhagic diarrhea. C. liver failure. D. hemorrhagic diarrhea, liver failure, and brain damage.

B

Which of the following is NOT characteristic of a coliform? A. gram-negative B. resistant to chlorination C. rod shaped D. facultatively aerobic

B

Which of the following pathogens is spread by infected lice? A. Borrelia burgdorferi B. Rickettsia prowazekii C. Plasmodium falciparum D. Yersinia pestis

B

Which of the following are properties of exotoxins? Select all that apply. A. Exotoxins are released from the cell during death or replication. B. Exotoxins target specific cellular structures or molecules. C. Very small amounts of exotoxin can be lethal. D. Exotoxins are produced primarily by gram-negative bacteria. E. Exotoxins are protein molecules. F. Exotoxins are extremely heat stable.

B, C, E

The primary disease reservoir for plague is: A. rats. B. humans. C. fleas. D. mosquitoes.

A

Vibrio cholerae is a human pathogen that causes cholera. It has an unusual shape distinctive of its genus. Considering that it does not have one of the most common bacterial shapes, what is the shape of this species? A. a curved rod B. a rigid spiral shape C. a spherical shape D. a straight rod

A

Animal diseases transmissible to humans are known as: A. zoonoses. B. vectors. C. radicals. D. ferals.

A

Clostridium tetani is an obligate anaerobe that can cause tetanus. When it enters the human body, it can produce tetanus toxin. Considering that C. tetani is an obligate anaerobe, which of the following explains how it can survive and cause disease in the human body? A. Especially in deep wounds, C. tetani can sometimes survive in areas with damaged tissue and poor to no blood flow. B. It doesn't survive; it simply releases toxin as it dies. C. C. tetani can only survive when other bacteria are available to consume oxygen and to keep oxygen levels low. D. C. tetani can't access atmospheric oxygen, so it can grow as long as it stays on the surface of the skin rather than in well-oxygenated deeper tissues.

A

In bubonic plague, buboes are swellings formed in the lymph nodes and filled with: A. Yersinia pestis. B. Xenopsylla cheopis. C. Rickettsia prowazekii. D. Clostridium tetani.

A

In the United States, individuals become infected with Vibrio cholerae most commonly by: A. consuming contaminated shellfish. B. person-to-person contact. C. eating contaminated vegetables. D. drinking contaminated water.

A

Lyme disease and syphilis are similar in that they __________. A. are both caused by spirochetes and are chronic infections that involve the nervous systems B. are both chronic infections that involve the nervous system C. are both contracted by person-to-person contact D. are both caused by spirochetes

A

Many West Nile virus infections are not properly identified because: A. the symptoms are often subacute. B. the disease mimics malaria. C. most physicians and diagnosticians are not aware of this disease. D. the disease is frequently fatal.

A

Of the arthropod-borne diseases, there is a vaccine to prevent __________. A. yellow fever B. West Nile fever C. dengue fever D. Lyme disease

A

Severe cases of Staphylococcus aureus food poisoning may require treatment: A. for dehydration. B. with cleansing enemas. C. with powerful antibiotics. D. for dehydration, along with powerful antibiotics and cleansing enemas.

A

Tests to monitor water safety often report the number of fecal coliform bacteria found in samples. Which of the following statements accurately reflects water safety recommendations based upon fecal coliform levels? A. If the level of fecal coliform bacteria is low, then the water may still be unsafe because of the presence of other pathogens. B. If the level of fecal coliform bacteria is low, then the water was probably contaminated by sewage. C. If the level of fecal coliform bacteria is high, then the water is safe for drinking and recreational purposes. D. If the level of fecal coliform bacteria is high, then the water is safe for drinking and recreational purposes.

A

The MOST common source of individual foodborne botulism outbreaks are due to consumption of: A. nonacid, home-canned vegetables. B. dairy products. C. egg and meat salads. D. honey.

A

The MOST important potential common source of infectious disease is: A. water. B. industrial waste. C. human and animal wastes. D. arthropod reservoirs found near surface water supplies.

A

The most severe and fatal form of anthrax is: A. inhalation anthrax. B. intestinal anthrax. C. cutaneous anthrax. D. zoonotic anthrax.

A

Disease research and epidemiology bring together many different facets to help us better understand disease pathology and spread. Which of the following statements are true? Select all that apply. A. Bacterial exotoxins can be altered to create toxoids, which can be used to produce protective immunity in a host. B. The ID50 value refers to the number of microbes needed to cause half of an infected population to die. C. The terms pathogenicity and virulence can be used interchangeably to describe the severity of an infection. D. Some pathogens are able to cause disease within a host without penetrating the body. E. Intoxications result from a bacterial infection in which a large amount of bacterial toxin is produced. F. The interactions that occur between a microbe and host influence the evolution of both.

A, D, F

Borrelia burgdorferi is an interesting spirochete that is unusual when compared to other bacteria. Which of the following is the reason that it is so unusual? A. it has a cell wall B. it has a linear chromosome C. it has ribosomes D. it has flagella

B

Clostridium botulinum is a gram- ________ rod that produces an ________. A. negative / exotoxin B. positive endospore-forming / exotoxin C. negative / endotoxin D. positive endospore-forming / endotoxin

B

Coliforms in a water sample indicate ________ contamination. A. arthropod B. fecal C. industrial or chemical D. All of the answers are correct.

B

Food that is heavily salted or candied does not need to be refrigerated. Why not? A. Extremely concentrated solutions are very hypotonic and cause microbes to desiccate. As a result, there is no need for lower temperatures through refrigeration to slow growth. B. Extremely concentrated solutions are very hypertonic and therefore desiccate microorganisms. As a result, there is no need for lower temperatures through refrigeration to slow growth. C. The sugar used is of a type that cannot be used by microbes, leaving a lack of suitable nutrition for them. As a result, there is no need for refrigeration to slow growth. D. Having a high concentration of salt or sugar lowers the food's pH, making it too acidic for common pathogens to grow. As a result, there is no need for refrigeration to slow growth.

B

A person is MOST likely to contract diseases such as Rocky Mountain spotted fever and ehrlichiosis if he or she visits/participates in: A. metropolitan cities. B. European countries. C. camping and hiking in the backcountry. D. snow skiing.

C

A student travels to Brazil by boat on the Amazon River, without visiting the doctor prior to traveling for recommended vaccinations for travel to South America. The student becomes ill during the trip and is quarantined. Which of the diseases listed below does the student most likely have? A. Ebola B. hantavirus C. yellow fever D. Q fever

C

Although cholera can be treated with antibiotics, data suggest that antibiotic treatment alone is NOT the most effective therapy. Which of the following statements describes the most likely reason for supplementing antibiotic therapy? A. As with V. cholerae, the acidic environment of the stomach can have a negative impact on antibiotic activity. B. The production of cholera toxin helps V. cholerae resist antibiotic treatment. C. Antibiotic therapy addresses only the growth of V. cholerae; it doesn't address the extreme dehydration suffered by a person infected with V. cholerae. D. Because V. cholerae is a gram-negative organism, it is not very effectively treated with antibiotics.

C

At what temperature are most household freezers kept? A. 4°C B. -80°C C. -20°C D. 0°C

C

Salmonellosis is most frequently caused by Salmonellosis is most frequently caused by: A. Salmonella enterica serovar Typhimurium. B. Salmonella enterica serovar Enteritidis. C. Salmonella enterica serovars Typhimurium and Enteritidis. D. Salmonella enterica serovar Typhi.

C

Soldiers or refuges in crowded unsanitary conditions are MOST susceptible to which rickettsial disease? A. Q fever B. Rocky Mountain spotted fever C. typhus D. Lyme disease

C

Controlling most rickettsial diseases involves managing: A. immunization strategies. B. human behavior. C. food safety procedures. D. the vector.

D

Hantaviruses are most commonly transmitted by ________ of virus-contaminated rodent ________. A. ingestion / saliva B. ingestion / excreta C. inhalation / saliva D. inhalation / excreta

D

Some studies have indicated that the ID50 for Vibrio cholerae can be as high as 108 organisms. Which of the following most likely explains the requirement for this relatively high ID50? A. Because the major virulence factor of V. cholerae is cholera toxin, large numbers of bacteria are required to produce enough toxin to cause disease. B. V. cholerae does not produce enough virulence factors to overcome the host response and cause disease. C. To establish infection, V. cholerae must survive the host immune response and the acidic environment of the stomach. D. Because V. cholerae cells are relatively small compared to host cells, thousands of bacteria must infect each cell to cause disease.

C

Which of the following bacterial pathogens is found in aquatic environments and is commonly present in air conditioning systems? A. Enterobacter aerogenes B. Klebsiella pneumoniae C. Legionella pneumophila D. Vibrio cholerae

C

Which of the following would be the best strategy to prevent the spread of yellow fever and dengue fever into the southern United States? A. vaccination B. tick avoidance C. mosquito avoidance and eradication D. monitoring bird populations

C

The ability of Vibrio cholerae to cause disease depends on a number of factors. Which of the following are requirements for causing disease within a host? Select all that apply. A. depleting the host of nutrients at the site of infection B. direct damage of host tissues C. gaining access to the host via a portal of entry D. adherence to host tissues E. evasion of host defenses F. production of exotoxins

C, D, E

Animal-transmitted diseases are generally spread to accidental hosts by: A. aerosols. B. direct contact. C. bites. D. direct contact, aerosols, and bites.

D

Staphylococcus aureus is a common foodborne disease, because it: A. is present in some humans that work in food processing. B. grows on common foods. C. produces several heat-stable enterotoxins. D. grows on many foods, is present in some humans that work in food processing, and produces several heat-stable enterotoxins.

D

The causative agent of Lyme disease is ________, which is carried primarily by the ________. A. Yersinia pestis / Xenopsylla cheopis (rat flea) B. Rickettsia prowazekii / Culex species (mosquito) C. a flavivirus / Ixodes sp. (deer tick) D. Borrelia burgdorferi / Ixodes sp. (deer tick)

D

The principle behind salt or sugar preservation is to: A. accomplish all of the described functions depending on the food being preserved. B. introduce a mechanical barrier to microbial invasion. C. introduce a microbicide in anticipation of contaminating bacteria or fungi. D. reduce water activity (aw).

D

The rate of contaminant microbial growth during the exponential phase in food depends on: A. temperature. B. the nutrient value of the food. C. water content. D. temperature, nutrient value, and water content.

D

What type of diseases require biosafety level (BSL) 4 procedures and facilities when working with samples that may be infected? A. diseases with high mortality B. diseases for which no treatment or vaccine exist C. highly infectious diseases D. highly infectious diseases with high mortality for which no treatment or vaccine exis

D

Which of the following explains why treatment of symptomatic tetanus requires an antitoxin and an antibiotic? A. It is always better to use multiple treatments to elicit a stronger response. B. The tetanus toxin binds irreversibly, causing damage to axons. The only way to heal the axons is with an antitoxin. C. Because the toxin is within the cell wall of the bacteria, it can only be eliminated by killing the bacteria. D. Because C. tetani bacteria excrete tetanus toxin, it is important to neutralize the toxin while also killing the bacteria that are producing more.

D

T/F Erythema migrans is associated with typhus.

F

T/F Cholera can be transmitted by water or food

T

T/F Not all coliforms are pathogenic.

T

T/F Various Ixodes spp., as well as various Borrelia spp., may be involved in the transmission and cause of Lyme disease.

T