 |
| 1 | |
In nature, all organisms, including humans and microbes, interact with one another as part of a biological community called |
| | A) | microbiota. |
| | B) | a universe. |
| | C) | transient flora. |
| | D) | an ecosystem. |
|
|
|
| 2 | |
The type of symbiotic relationship Escherichia coli exhibits with the normal human host is best referred to as |
| | A) | commensalism. |
| | B) | mutualism. |
| | C) | parasitism. |
| | D) | none of the above. |
|
|
|
| 3 | |
People who have substantial meat in their diet will have more ______________ in their large intestine than those who have a predominantly vegetarian diet. |
| | A) | Bacteroides. |
| | B) | Staphylococcus. |
| | C) | Escherichia. |
| | D) | Pseudomonas. |
|
|
|
| 4 | |
When a parasitic organism grows and multiplies on or in the body of the host, a state of _____________ exists. |
| | A) | disease. |
| | B) | secondary complication. |
| | C) | infection. |
| | D) | quality health. |
|
|
|
| 5 | |
Organisms that cause disease only when introduced into an unusual location or into an immunologically compromised host may best be classified as |
| | A) | avirulent. |
| | B) | pathogens. |
| | C) | opportunist pathogens. |
| | D) | latent pathogens. |
|
|
|
| 6 | |
Organisms such as rickettsia or viruses may be described as |
| | A) | obligate intracellular parasites. |
| | B) | facultative pathogens. |
| | C) | extracellular parasites. |
| | D) | avirulent. |
|
|
|
| 7 | |
One would expect microbes to be found in each of the following areas EXCEPT the |
| | A) | large intestine. |
| | B) | oral cavity. |
| | C) | blood. |
| | D) | urine. |
|
|
|
| 8 | |
When classifying the effects of a disease, one would classify a rash as a |
| | A) | symptom. |
| | B) | sign. |
| | C) | virulence factor. |
| | D) | none of the above. |
|
|
|
| 9 | |
When symptoms do not occur or are mild enough to go unnoticed, the infection may be |
| | A) | subclinical. |
| | B) | acute. |
| | C) | chronic. |
| | D) | focal. |
|
|
|
| 10 | |
The transmission of Hepatitis B virus by the stick of a needle is an example of which of the following modes of transmission? |
| | A) | direct contact. |
| | B) | vector. |
| | C) | airborne. |
| | D) | fomite. |
|
|
|
| 11 | |
This part of the bacterial cell wall is responsible for the toxic properties of the endotoxin produced by some bacteria. |
| | A) | O antigen. |
| | B) | K antigen. |
| | C) | H antigen. |
| | D) | lipid A. |
|
|
|
| 12 | |
A type of cytolytic toxin that destroys red blood cells is called |
| | A) | lipase. |
| | B) | hemolysin. |
| | C) | leukocidin. |
| | D) | streptokinase. |
|
|
|
| 13 | |
The transfer of genetic material from one strain of bacteria to another may be accomplished by a process of bacterial-viral transfer known as |
| | A) | conjugation. |
| | B) | transformation. |
| | C) | transduction. |
| | D) | none of the above. |
|
|
|
| 14 | |
Fungi in the normal flora, such as the yeast Candida albicans are capable of causing disease in the compromised host. An example of a compromised host would be a |
| | A) | diabetic patient. |
| | B) | newborn infant. |
| | C) | patient receiving antibiotic treatment. |
| | D) | all of the above. |
|
|
|
| 15 | |
Adenovirus has genes that suppress expression of class I MHC and thus evade being targeted by |
| | A) | T cells. |
| | B) | B cells. |
| | C) | enzymes. |
| | D) | lytic factors. |
|
|
|
| 16 | |
An example of an infection that is not communicable would be |
| | A) | Streptococcus infections. |
| | B) | Staphylococcus infections. |
| | C) | Clostridium infections. |
| | D) | HIV infections. |
|
|
|
| 17 | |
If a child has chickenpox and contracts a staphylococcal infection associated with the pox, the staphylococcal infection would be classified as |
| | A) | primary. |
| | B) | secondary. |
| | C) | subacute. |
| | D) | chronic. |
|
|
|
| 18 | |
The outcome of an infection depends on the |
| | A) | virulence of the pathogen. |
| | B) | response of the host. |
| | C) | both A and B are correct. |
| | D) | neither A nor B is correct. |
|
|
|
| 19 | |
An immunosuppressive response of stress is the production of |
| | A) | complement. |
| | B) | catecholamines. |
| | C) | proteases. |
| | D) | corticosteroid hormones. |
|
|
|
| 20 | |
In this type of symbiotic relationship, one partner benefits while the other is unaffected. |
| | A) | parasitism. |
| | B) | commensalism. |
| | C) | mutualism. |
| | D) | none of the above. |
|
|
|
| 21 | |
A study in Central America showed that the diarrhea-causing bacteria survive better when found growing with large populations of aquatic fungi. Which of the following statements best explains this observation? |
| | A) | The bacteria are parasitic on the fungi. |
| | B) | The fungi are parasitic on the bacteria. |
| | C) | This is obviously an example of mutualism. |
| | D) | The fungi somehow help the bacteria through commensalisms or mutualism. |
| | E) | The bacteria and fungi are in a competitive relationship. |
|
|
|
| 22 | |
Food sterilization studies have shown that killing bacteria found on foods does not always prevent illness caused by contaminated food. Which of the following is the best explanation for this observation? |
| | A) | The bacteria may leave behind endotoxins not destroyed by sterilization. |
| | B) | Dead bacteria can still release exotoxins. |
| | C) | Not all the bacteria are killed by sterilization. |
| | D) | Sterilization leaves behind bacterial enzymes capable of doing harm. |
| | E) | None of the above. |
|
|
|
| 23 | |
Agricultural researchers are using genetic engineering for developing creative ways to protect livestock from infectious diseases that affect food safety. In one strategy scientists inoculate animals with genetically engineered bacteria that do not cause disease. It is hoped that the genetically altered bacteria will displace the pathogenic bacteria, colonizing the animals with bacteria that do not harm the animals or humans. Which of the following would be an effective way to carry out this strategy? |
| | A) | Altering E. coli so that they do not digest starch. |
| | B) | Altering Salmonella so they do not fuse with the phagosome. |
| | C) | Altering Shigella so that they make a variety of surface antigens. |
| | D) | Altering E. coli so that they cannot undergo conjugation. |
| | E) | Altering Shigella and Salmonella so they cannot dissolve the phagosome membrane. |
|
|
|
| 24 | |
Mutations to which of the following types of genes would likely have the largest effect on changing the pathogenicity of bacteria? |
| | A) | Digestive enzyme genes. |
| | B) | Antibiotic resistance genes. |
| | C) | Pathogenicity island genes. |
| | D) | Surface antigen genes. |
| | E) | Superantigen genes. |
|
|
|
| 25 | |
Which is probably the best way to control pathogenic bacteria that cause disease in animals and humans? |
| | A) | Developing drugs that block exotoxin action. |
| | B) | Developing drugs that block endotoxin action. |
| | C) | Developing drugs that block superantigen action. |
| | D) | Developing drugs that prevent invasion. |
| | E) | Developing strategies that reduce bacterial transmission. |
|
|
.