Q1) Which of the following organisms is photoautotrophic protozoan?

A) oomycote

B) cellular slime mold

C) Euglena

D) Phytophthora

E) plasmodial slime mold

Q2) Which of the following pairs is mismatched?

A) tick - Rocky Mountain spotted fever

B) tick - Lyme disease

C) mosquito - malaria

D) mosquito - Pneumocystis

E) mosquito - encephalitis

Q3) Which of the following groups of algae does NOT produce compounds that are toxic to humans?

A) diatoms

B) dinoflagellates

C) green algae

D) red algae

E) None of the answers is correct; all of these groups of algae produce compounds toxic to humans.

Q4) The cells of plasmodial slime molds can grow to several centimeters in diameter because

A) they have organelles.

B) they distribute nutrients by cytoplasmic streaming.

C) the large surface can absorb nutrients.

D) they form spores.

E) they have a mouth to ingest nutrients.

Q5) Assume you have isolated a multicellular heterotrophic organism that produces coenocytic hyphae, motile zoospores, and cellulose cell walls. It is most likely a(n)

A) ascomycete fungus.

B) green alga.

C) oomycote alga.

D) tapeworm.

E) zygomycete fungus.

Q6) If a larva of Echinococcus granulosus is found in humans, humans are the

A) definitive host.

B) infected host.

C) intermediate host.

D) reservoir.

E) None of the answers is correct.

Q7) Ringworm is caused by a(n)

A) fungus.

B) cestode.

C) nematode.

D) protozoan.

E) trematode.

Q8) Yeast infections are caused by

A) Aspergillus.

B) Candida albicans.

C) Histoplasma.

D) Penicillium.

E) Saccharomyces cerevisiae.

Q9) All of the following are characteristic of lichens EXCEPT

A) they are arranged in foliose, fruticose, or crustose morphologies.

B) they are a major food source for tundra herbivores.

C) they are used as indicators of air pollution.

D) they are a symbiotic relationship between a fungus and a protozoan.

E) they serve as primary producers in rocky ecosystems.

Q10) You see acid-fast oocysts in a fecal sample from a patient who has diarrhea. What is the MOST likely cause?

A) Cryptosporidium

B) diatoms

C) Entamoeba

D) Giardia

E) Taenia

Q11) The most frequently used portal of entry for pathogens is the

A) mucous membranes of the respiratory tract.

B) mucous membranes of the gastrointestinal tract.

C) skin.

D) parenteral route.

E) All of these portals are used equally.

Q12) The ability of some microbes, such as Trypanosoma or Giardia to alter their surface molecules and evade destruction by the host's antibodies is called

A) antigenic variation.

B) lysogenic conversion.

C) virulence.

D) cytopathic effect.

E) cytocidal effect.

Q13) Most pathogens that gain access through the skin

A) can penetrate intact skin.

B) just infect the skin itself.

C) enter through hair follicles and sweat ducts.

D) must adhere first while their invasive factors allow them to penetrate.

E) must be injected.

Q14) All of the following contribute to a pathogen's invasiveness EXCEPT

A) toxins.

B) capsules.

C) cell wall components.

D) hyaluronidase.

E) coagulases.

Q15) Which of the following statements is FALSE?

A) Leukocidins destroy neutrophils.

B) Hemolysins lyse red blood cells.

C) Hyaluronidase breaks down substances between cells.

D) Kinase destroys fibrin clots.

E) Coagulase destroys blood clots.

Q16) Which of the following statements about exotoxins is generally FALSE?

A) They are more potent than endotoxins.

B) They are composed of proteins.

C) They are resistant to heat.

D) They have specific methods of action.

E) They are produced by gram-positive bacteria.

Q17) Endotoxins are

A) associated with gram-positive bacteria.

B) molecules that bind nerve cells.

C) part of the gram-negative cell wall.

D) excreted from the cell.

E) A-B toxins.

Q18) Cytopathic effects are changes in host cells due to

A) viral infections.

B) protozoan infections.

C) fungal infections.

D) bacterial infections.

E) helminthic infections.

Q19) Which of the following does NOT contribute to the symptoms of a fungal disease?

A) capsules

B) toxins

C) allergic response of the host

D) cell walls

E) metabolic products

Q20) All of the following are methods of avoiding host antibodies EXCEPT

A) antigenic changes.

B) IgA proteases.

C) invasins.

D) membrane-disrupting toxins.

E) inducing endocytosis.

Q21) The fimbriae of Neisseria gonorrhea and enteropathogenic E. coli are examples of

A) adhesins.

B) ligands.

C) receptors.

D) adhesins and ligands.

E) adhesins, ligands, and receptors.

Q22) Superantigens produce intense immune responses by stimulating lymphocytes to produce

A) endotoxins.

B) exotoxins.

C) cytokines.

D) leukocidins.

E) interferons.

Q23) Botulism is caused by ingestion of a proteinaceous exotoxin; therefore, it can easily be prevented by

A) boiling food prior to consumption.

B) administering antibiotics to patients.

C) not eating canned food.

D) preventing fecal contamination of food.

E) filtering food.

Q24) Symptoms of protozoan and helminthic diseases are due to

A) tissue damage due to growth of the parasite on the tissues.

B) waste products excreted by the parasite.

C) products released from damaged tissues.

D) tissue damage due to growth of the parasite on the tissues and waste products excreted by the parasite.

E) tissue damage due to growth of the parasite on the tissues, waste products excreted by the parasite, and products released from damaged tissues.

Q25) Which of the following statements about staphylococcal enterotoxin is FALSE?

A) It causes vomiting.

B) It causes diarrhea.

C) It is an exotoxin.

D) It is produced by Staphylococcus aureus growing in the host's intestines.

E) It is a superantigen.

Q26) Which of the following contributes to the virulence of a pathogen?

A) numbers of microorganisms that gain access to a host

B) evasion of host defenses

C) toxin production

D) numbers of microorganisms that gain access to a host and evasion of host defenses

E) numbers of microorganisms that gain access to a host, evasion of host defenses, and toxin production

Q27) Lysogenic bacteriophages contribute to bacterial virulence because bacteriophages

A) give new gene sequences to the host bacteria.

B) produce toxins.

C) carry plasmids.

D) kill the bacteria, causing release of endotoxins.

E) kill human cells.

Q28) Twenty-five people developed symptoms of nausea, vomiting, and diarrhea three to six hours after attending a church picnic where they ate a ham and green bean casserole with cream sauce. The most likely cause of this case of food intoxication is

A) botulinum toxin.

B) aflatoxin.

C) staphylococcal enterotoxin.

D) erythrogenic toxin.

E) cholera toxin.

Q29) Symptoms of intense inflammation and shock occur in some gram-positive bacterial infections due to

A) A-B toxins.

B) lipid A.

C) membrane-disrupting toxins.

D) superantigens.

E) erythrogenic toxin.

Q30) Which of the following mechanisms is used by gram-negative bacteria to cross the blood-brain barrier?

A) producing fimbriae

B) inducing endocytosis

C) producing toxins

D) inducing TNF

E) antigenic variation

Q31) Injectable drugs are tested for endotoxins by

A) the Limulus amoebocyte lysate test.

B) counting the viable bacteria.

C) filtering out the cells.

D) looking for turbidity.

E) culturing bacteria.

Q32) Endotoxins in sterile injectable drugs could cause

A) infection.

B) septic shock symptoms.

C) giant cell formation.

D) nerve damage.

E) no damage, because they are sterile.