Final Exam Cumulative Review

Herpesvirus infections can be controlled with chemotherapeutic agents.

T

M protein is a virulence factor associated with group A streptococci.

T

Smallpox vaccination was originally discontinued in the 1980's because of adverse effects of the vaccine.

T

"Ringworm" is caused by a) parasitic worms that infect the skin b) immunosuppression due to HIV infection c) a hypersensitivity reaction caused by superficial contact with dermatophytes d) dermatophytes that have invaded deep layers of the skin e) dermatophytes growing in upper dead tissue layers of the skin

E

A sample from an abscess is stained and examined under the microscope. A Gram stain appears uniformly pink, but a GMS (Gomori methenamine sliver) stain reveals brownish filaments in the sample. These findings suggest a) sporotrichosis b) necrotizing fasciitis c) dermatophytosis d) leishmaniasis e) phaeohyphomycosis

E

Common skin warts are the result of infection with a) herpesviruses b) moriliviruses c) coxsackieviruses d) poxviruses e) papillomaviruses

E

Erythema infectiosum is also known as a) roseola b) three-day measles c) rubeola d) herpangina e) fifth disease

E

Necrotizing fasciitis is caused by a) Pseudomonas aeruginosa b) Staphylococcus aureus c) Rickettsia rickettsii d) Streptococcus pyogenes e) both Streptococcus pyogenes ans Staphylococcus aureus

E

One feature that differentiates Staphylococcus aureus from other staphylococci is its a) beta-lactamase production b) slime layer production c) coagulase production d) production of both a slime layer and coagulase e) production of both coagulase and beta-lactamase

E

Which of the following is an INCORRECT pairing? a) HHV-6 : roseola b) variola : smallpox c) German measles : rubella d) measles : rubeola e) herpes zoster : genital warts

E

Which of the following is becoming rarer as a result of childhood vaccinations? a) warts b) roseola c) impetigo d) neonatal herpes e) subacute sclerosing panencephalitis

E

Which of the following is/are anti-phagocytic? a) protein A b) leukocidin c) M protein d)both protein A and M protein e)protein A, M protein, and lekocidin

E

Which infection is caused by S. aureus? A) Pimples B) Sty C) Furuncle D) Carbuncle E) All of the above

E) All of the above

Which of the following causes opportunistic infections in AIDS patients? A) Pneumocystis B) Aspergillus C) Rhizopus D) Mucor E) All of the above

E) All of the above

Which of the following is not a characteristic of Bacillus anthracis? A) Aerobic B) Gram-positive C) Forms endospores D) Found in soil E) All of the above are characteristics of B. anthracis

E) All of the above are characteristics of B. anthracis

Which of the following pairs is not correctly matched for Gram reaction? A) Lyme disease gram-negative B) Tularemia gram-negative C) Anthrax gram-positive D) Rocky Mountain spotted fever gram-negative E) All of the above are correctly matched

E) All of the above are correctly matched

A healthy carrier state exists for A) Corynebacterium diphtheriae. B) Streptococcus pneumoniae. C) Beta-hemolytic streptococci. D) Haemophilus influenzae. E) All of the above.

E) All of the above.

A person can have a positive tuberculin skin test because A) She has been vaccinated. B) She has tuberculosis. C) She had tuberculosis. D) She is immune to tuberculosis. E) All of the above.

E) All of the above.

Newbornsʹ eyes are treated with an antibiotic when A) N. gonorrhoeae is isolated from the eyes. B) The mother is blind. C) The mother has genital herpes. D) The mother has gonorrhea. E) Always.

E) Always.

The symptoms of gas gangrene are due to all of the following except A) Microbial fermentation. B) Necrotizing exotoxins. C) Proteolytic enzymes. D) Hyaluronidase. E) Anaerobic environment.

E) Anaerobic environment.

A vaccine is available for all of the following except A) Haemophilus meningitis. B) Neisseria meningitis. C) Tetanus. D) Rabies. E) Botulism.

E) Botulism.

The patient has a sore throat. What is the etiology? A) Corynebacterium B) Haemophilus C) Bordetella D) Mycobacterium E) Canʹt tell

E) Canʹt tell

Which of the following pairs is mismatched? A) Malaria Anopheles (mosquito) B) Dengue Aedes (mosquito) C) Epidemic typhus Pediculus (louse) D) Rocky Mountain spotted fever Dermacentor (tick) E) Encephalitis Ixodes (tick)

E) Encephalitis Ixodes (tick)

The symptoms of trichinellosis are due to the A) Growth of larval Trichinella in the large intestine. B) Growth of adult Trichinella in the large intestine. C) Formation of cysticerci. D) Encystment of adult Trichinella in muscles. E) Encystment of larval Trichinella in muscles.

E) Encystment of larval Trichinella in muscles.

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

E) Entamoeba histolytica

In which of the following respects is measles similar to German measles? A) Rash B) Etiologic agent C) Encephalitis as a complication D) Congenital complications E) In name only

E) In name only

4) All of the following are true about H. influenzae, except A) A healthy carrier state can exist. B) It is encapsulated. C) It requires a blood supplement in media. D) It usually infects children. E) It is used in a whole bacterial vaccine.

E) It is used in a whole bacterial vaccine.

All of the following statements about tularemia are true except A) It is caused by Francisella tularensis. B) The reservoir is rabbits. C) It may be transmitted by arthropods. D) It may be transmitted by direct contact. E) It occurs only in California.

E) It occurs only in California.

3) Which of the following organisms is not capable of causing meningitis? A) Neisseria meningitidis B) Haemophilus influenzae C) Cryptococcus neoformans D) Streptococcus pneumoniae E) None of the above

E) None of the above

Used to treat smallpox. A) Penicillin B) Sulfonamide C) Trifluridine D) Fungicide E) None of the above

E) None of the above

Which of the following pairs is mismatched? A) Q fever ticks B) Psittacosis parrots C) Pneumocystis pneumonia nosocomial D) Coccidioides soil E) None of the above

E) None of the above

Which of the following pairs is mismatched? A) S. aureus impetigo B) S. pyogenes erysipelas C) P. acnes acne D) P. aeruginosa otitis externa E) None of the above

E) None of the above

All of the following grow inside host cells except A) Babesia. B) Brucella. C) Dengue fever virus. D) Leishmania. E) None of the above.

E) None of the above.

All of the following statements about schistosomiasis are true except A) The cercariae penetrate human skin. B) A parasite of birds causes swimmerʹs itch in humans. C) The intermediate host is an aquatic snail. D) It is caused by a flatworm. E) None of the above.

E) None of the above.

Pneumonia can be caused by all of the following except A) Legionella. B) Haemophilus. C) Mycoplasma. D) Streptococcus. E) None of the above.

E) None of the above.

Relapsing fever and undulant fever differ in all of the following ways except A) Mode of transmission. B) Presence of rash. C) Reservoir. D) Etiology. E) None of the above.

E) None of the above.

Septicemia may result from all of the following except A) A focal infection. B) Pneumonia. C) A nosocomial infection. D) Contamination through the parenteral route. E) None of the above.

E) None of the above.

Vaccination for rubella is A) Not necessary because the disease is mild. B) Not necessary if a person has had an infection. C) Recommended only for pregnant women. D) Recommended for newborns to prevent congenital disease. E) None of the above.

E) None of the above.

Microscopic examination of a lung biopsy shows thick-walled cysts. What is the etiology? A) Blastomyces B) Coccidioides C) Histoplasma D) Mycobacterium E) Pneumocystis

E) Pneumocystis

All of the following are eukaryotes that cause gastroenteritis except A) Cryptosporidium. B) Cyclospora. C) Entamoeba. D) Giardia. E) Pneumocystis.

E) Pneumocystis.

6) Which of the following organisms is not correctly matched to the recommended treatment? A) Neisseria meningitidis cephalosporins B) Haemophilus influenzae cephalosporins C) Cryptococcus neoformans amphotericin B D) Mycobacterium leprae dapsone E) Poliovirus Salk vaccine

E) Poliovirus Salk vaccine

All of the following are caused by prions except A) Sheep scrapie. B) Kuru. C) Creutzfeldt-Jakob disease. D) Transmissible mink encephalopathy. E) Rabies.

E) Rabies.

The patient has a papular rash. Microscopic examination of skin scrapings reveals small 8-legged animals. A) Candida B) Microsporum C) P. aeruginosa D) S. aureus E) Scabies

E) Scabies

A patient who presents with red throat and tonsils can be diagnosed as having A) Streptococcal pharyngitis. B) Scarlet fever. C) Diphtheria. D) Common cold. E) There is insufficient information.

E) There is insufficient information.

Which of the following pairs regarding the epidemiology of malaria is mismatched? A) Vector Anopheles B) Etiology Plasmodium C) Found in liver sporozoites D) Diagnosis presence of merozoites E) Treatment antibiotics

E) Treatment antibiotics

A 45-year-old male has pus-filled vesicles distributed over his back in the upper right quadrant, over his right shoulder, and upper right quadrant of his chest. His symptoms are most likely due to A) Candida albicans. B) Herpes simplex virus. C) Staphylococcus aureus. D) Streptococcus pyogenes. E) Varicella-zoster virus.

E) Varicella-zoster virus.

Because they are common soil saprobes, dermatophytes are fungi that are not contagious in humans.

F

Chromoblastomycosis is rarely a severe disease and can be treated easily with appropriate drugs.

F

Clostridium perfringens causes necrotizing fasciitis.

F

Humans are the only hosts of Rickettsia rickettsii.

F

In pregnant women, roseola infection can result in teratogenic birth defects.

F

Mucocutaneous leishmaniasis, also known as kala-azar, is fatal in 100% of untreated cases.

F

A 38-year-old man had onset of fever, chills, nausea, and myalgia. On April 29, he had eaten raw oysters. 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 alcoholic liver disease. He was transferred to the ICU; therapy with ciprofloxacin was initiated. On May 4, he died. Which of the following is the most likely etiology? A) Bacillus cereus B) Cyclospora C) Salmonella D) Vibrio vulnificus E) Yersinia enterocolitica

D) Vibrio vulnificus

All of the following are treated with antibiotics except A) Plague. B) Tularemia. C) Lyme disease. D) Yellow fever. E) None of the above.

D) Yellow fever.

A) Lactobacillus.

1) Normal microbiota of the adult vagina consist primarily of A) Lactobacillus. B) Streptococcus. C) Mycobacterium. D) Neisseria. E) Candida.

21) Three weeks after a river rafting trip, three family members experienced symptoms of coughing, fever, and chest pain. During the rafting trip, the family had consumed crayfish that they caught along the river banks. An examination of the patients' sputum revealed helminth eggs, and serum samples were positive for antibodies to Paragonimus. All of the family members recovered following treatment with praziquantel. In the Paragonimus life cycle, A) the crayfish are the definitive host and humans are the intermediate host. B) humans are the definitive host and crayfish are the intermediate host. C) both humans and crayfish are intermediate hosts. D) both humans and crayfish are definitive hosts. E) the source of the infection was the river water.

Answer: B

21) Which of the following antibiotics are used to treat fungal infections? 1. aminoglycosides 2. cephalosporins 3. griseofulvin 4. polyenes 5. bacitracin A) 1, 2, and 3 B) 3 and 4 C) 3, 4, and 5 D) 4 and 5 E) All of these antibiotics are used to treat fungal infections.

Answer: B

22) A virus's ability to infect an animal cell depends primarily upon the A) host cell's ability to phagocytize viral particles. B) presence of receptor sites on the cell membrane. C) type of viral nucleic acid. D) enzymatic activity of a host cell. E) presence of pili on the host cell wall.

Answer: B

22) Assume you are growing bacteria on a lipid medium that started at pH 7. The action of bacterial lipases should cause the pH of the medium to A) increase. B) decrease. C) stay the same.

Answer: B

22) Most fungi grow best at pH A) 1. B) 5. C) 7. D) 9. E) 14.

Answer: B

22) The science that deals with when diseases occur and how they are transmitted is called A) ecology. B) epidemiology. C) communicable disease. D) morbidity and mortality. E) public health.

Answer: B

22) Which of the following antibiotics does NOT interfere with cell wall synthesis? A) cephalosporins B) macrolides C) natural penicillins D) semisynthetic penicillins E) vancomycin

Answer: B

23) A chill is a sign that A) body temperature is falling. B) body temperature is rising. C) body temperature is not changing. D) the metabolic rate is decreasing. E) blood vessels are dilating.

Answer: B

23) Serological testing is based on the fact that A) all bacteria have the same antigens. B) antibodies react specifically with an antigen. C) the human body makes antibodies against bacteria. D) antibodies cause the formation of antigens. E) bacteria clump together when mixed with any antibodies.

Answer: B

23) Which of the following terms describes NO3- → NO2- → N2O → N2? A) ammonification B) denitrification C) nitrification D) nitrogen fixation E) anaerobic respiration

Answer: B

24) A culture medium consisting of agar, peptone, and beef heart is a A) chemically defined medium. B) complex medium. C) selective medium. D) differential medium. E) reducing medium.

Answer: B

24) The mechanism whereby an enveloped virus leaves a host cell is called A) transduction. B) budding. C) abduction. D) lysogeny. E) penetration.

Answer: B

24) The terms "run" and "tumble" are generally associated with A) cell wall fluidity. B) taxic movements of the cell. C) clustering properties of certain rod-shaped bacteria. D) cell membrane synthesis.

Answer: B

24) Which microscope takes advantage of differences in the refractive indexes of cell structures? A) compound light microscope B) phase-contrast microscope C) darkfield microscope D) fluorescence microscope E) electron microscope

Answer: B

24) Which of the following uses glucose for carbon and energy? A) chemoautotroph B) chemoheterotroph C) photoautotroph D) photoheterotroph

Answer: B

25) Organism A has 70 moles % G+C, and organism B has 40 moles % G+C. Which of the following can be concluded from these data? A) The two organisms are related. B) The two organisms are unrelated. C) The organisms make entirely different enzymes. D) Their nucleic acids will completely hybridize. E) None of the answers is correct.

Answer: B

25) Which of the following is mismatched? A) diapedesis — movement of leukocytes between capillary walls cells out of blood and into tissue B) chemotaxis — chemical degradation inside a phagolysosome C) abcess — a cavity created by tissue damage and filled with pus D) pus — tissue debris and dead phagocytes in a white or yellow fluid E) scab — dried blood clot over injured tissue

Answer: B

25) Which of the following is the best definition of antigen? A) something foreign in the body B) a chemical that elicits an antibody response and can combine with these antibodies C) a chemical that combines with antibodies D) a pathogen E) a protein that combines with antibodies

Answer: B

25) Which of the following pairs is mismatched? A) psychrotroph — growth at 0°C B) thermophile — growth at 37°C C) mesophile — growth at 25°C D) psychrophile — growth at 15°C E) hyperthermophiles — growth at 85°C

Answer: B

26) All of the following are characteristic of algae EXCEPT A) most are photoautotrophs. B) they are classified as plants. C) they may be unicellular or multicellular. D) some produce harmful toxins. E) they mostly live in aquatic habitats.

Answer: B

26) All of the following are part of the mechanism of action of alpha and beta interferons EXCEPT A) they bind to the surface of uninfected cells. B) they are effective for long periods. C) they initiate manufacture of antiviral proteins. D) they disrupt stages of viral multiplication. E) they initiate transcription.

Answer: B

26) During which growth phase will gram-positive bacteria be most susceptible to penicillin? A) lag phase B) log phase C) death phase D) stationary phase E) The culture is equally susceptible during all phases.

Answer: B

26) The nonsulfur photosynthetic bacteria use organic compounds as A) carbon sources. B) electron donors to reduce CO2. C) energy sources. D) electron acceptors. E) oxygen sources.

Answer: B

26) Which of the following organisms would MOST likely be sensitive to natural penicillin? A) helminths B) Streptococcus pyogenes C) penicillinase-producing Neisseria gonorrhoeae D) Penicillium E) Mycoplasma

Answer: B

26) Which of the following pairs is mismatched? A) Ag — wound dressings B) alcohols — open wounds C) CuSO4 — algicide D) H2O2 — open wounds E) organic acids — food preservation

Answer: B

27) Which of the following is the best definition of generation time? A) the length of time needed for lag phase B) the length of time needed for a cell to divide C) the minimum rate of doubling D) the duration of log phase E) the time needed for nuclear division

Answer: B

28) Sedimentation of sludge occurs in A) anaerobic sludge digestion. B) primary sewage treatment. C) secondary sewage treatment. D) tertiary sewage treatment. E) water treatment.

Answer: B

28) Which of the following is an example of direct damage due to bacterial infection? A) the uncontrolled muscle contractions in Clostridium tetani infection B) the invasion and lysis of intestinal cells by E. coli C) the hemolysis of red blood cells in a staphylococcal infection D) the fever, nausea, and low blood pressure in a Salmonella infection E) the excessive secretion of fluids in a Vibrio cholera infection

Answer: B

29) Drug resistance occurs A) because bacteria are normal microbiota. B) when antibiotics are used indiscriminately. C) against antibiotics and not against synthetic chemotherapeutic agents. D) when antibiotics are taken after the symptoms disappear. E) All of the answers are correct.

Answer: B

29) Giardia and Trichomonas are unusual eukaryotes because they A) are motile. B) lack mitochondria. C) lack nuclei. D) do not produce cysts. E) do produce cysts.

Answer: B

29) Robert Koch identified the cause of A) smallpox. B) anthrax. C) diphtheria. D) AIDS. E) tuberculosis.

Answer: B

29) The product of which process contains the highest BOD? A) anaerobic sludge digestion B) primary sewage treatment C) secondary sewage treatment D) tertiary sewage treatment E) water treatment

Answer: B

29) Which group of microorganisms is most likely to spoil a freshwater trout preserved with salt? A) psychrophiles B) facultative halophiles C) anaerobes D) thermophiles E) hyperthermophiles

Answer: B

29) Which of the following criteria is most useful in determining whether two organisms are related? A) Both ferment lactose. B) Both are gram-positive. C) Both are motile. D) Both are aerobic. E) Each answer is equally important.

Answer: B

29) Which of the following places these items in the correct order for DNA-virus replication? 1. Maturation 2. DNA synthesis 3. Transcription 4. Translation A) 1; 2; 3; 4 B) 2; 3; 4; 1 C) 3; 4; 1; 2 D) 4; 1; 2; 3 E) 4; 3; 2; 1

Answer: B

3) A nosocomial infection is A) always present, but is inapparent at the time of hospitalization. B) acquired during the course of hospitalization. C) always caused by medical personnel. D) only a result of surgery. E) always caused by pathogenic bacteria.

Answer: B

3) If two organisms have similar rRNA sequences, you can conclude that they A) live in the same place. B) evolved from a common ancestor. C) will have different G-C ratios. D) will both ferment lactose. E) mated with each other.

Answer: B

3) Most of the available antimicrobial agents are effective against A) viruses. B) bacteria. C) fungi. D) protozoa. E) All of the answers are correct.

Answer: B

3) What type of immunity results from recovery from mumps? A) innate immunity B) naturally acquired active immunity C) naturally acquired passive immunity D) artificially acquired active immunity E) artificially acquired passive immunity

Answer: B

3) Which organism is NOT correctly matched to its energy source? A) photoheterotroph - light B) photoautotroph - CO2 C) chemoautotroph - Fe2+ D) chemoheterotroph - glucose E) chemoautotroph-NH3

Answer: B

30) A viral species is a group of viruses that A) has the same morphology and nucleic acid. B) has the same genetic information and ecological niche. C) infects the same cells and cause the same disease. D) cannot be defined.

Answer: B

30) Salmonella, Shigella, Yersinia, and Serratia are all A) pathogens. B) gram-negative facultatively anaerobic rods. C) gram-positive aerobic cocci. D) fermentative. E) endospore-forming bacteria.

Answer: B

30) Which of the following is TRUE about this reaction? NO3-+ 2H+ NO2- + H2O Nitrate ion Nitrite ion A) This process requires O2. B) This process occurs anaerobically. C) This process requires the electron transport system. D) This process requires light. E) This process requires O2 and the electron transport system.

Answer: B

B) Chlamydia trachomatis.

10) One form of NGU is lymphogranuloma venereum caused by A) Leptospira interrogans. B) Chlamydia trachomatis. C) Neisseria gonorrhoeae. D) Treponema pallidum. E) Candida albicans.

30) Which of the following is an organic growth factor? A) glucose B) vitamin B1 C) peptone D) NH4H2PO4 E) H2O

Answer: B

30) ________ is the physician first associated with vaccination. A) Pasteur B) Jenner C) Lister D) Koch E) Escherich

Answer: B

E) Lymphogranuloma venereum.

11) All of the following can cause congenital infections or infections of the newborn EXCEPT A) Syphilis. B) Gonorrhea. C) Nongonococcal urethritis. D) Genital herpes. E) Lymphogranuloma venereum.

C) Genital herpes

12) Which of the following recurs at the initial site of infection? A) Gonorrhea B) Syphilis C) Genital herpes D) Chancroid E) LGV

C) Syphilis

13) Which of the following is diagnosed by detection of antibodies against the causative agent? A) Nongonococcal urethritis B) Gonorrhea C) Syphilis D) Lymphogranuloma venereum E) Candidiasis

E) Neisseria gonorrhoeae.

14) Nongonococcal urethritis can be caused by all of the following EXCEPT A) Mycoplasma homini. B) Candida albicans. C) Trichomonas vaginalis. D) Streptococci. E) Neisseria gonorrhoeae.

C) Candidiasis

15) Which of the following is caused by an opportunistic pathogen? A) Trichomoniasis B) Genital herpes C) Candidiasis D) Gonorrhea E) Chancroid

C) Glycogen; lactic acid

16) The pH of the adult vagina is acidic due to the conversion of ________ to ________ by bacteria. A) Glucose; ethanol B) Protein; acetic acid C) Glycogen; lactic acid D) Mucosal cells; lactic acid E) Urine; lactic acid

C) Contains fewer than 10,000 pathogens/ml.

17) A normal urine sample collected by urinating into a sterile collection cup A) Is sterile. B) Contains fewer than 100 pathogens/ml. C) Contains fewer than 10,000 pathogens/ml. D) Contains more than 100,000 pathogens/ml. E) Has leukocyte esterase.

A) E. coli.

18) Most nosocomial infections of the urinary tract are caused by A) E. coli. B) Enterococcus. C) Proteus. D) Klebsiella. E) Pseudomonas.

Answer: B

19) Glomerulonephritis is A) Caused by Streptococcus pyogenes. B) An immune complex disease. C) Treated with penicillin. D) Transmitted by contaminated water. E) A and C

A) Escherichia coli.

2) Cystitis is most often caused by A) Escherichia coli. B) Leptospira interrogans. C) Candida albicans. D) Neisseria gonorrhoeae. E) Pseudomonas aeruginosa.

E) All of the above are predisposing factors.

20) Which of the following is NOT a predisposing factors to cystitis in females? A) The proximity of the anus to the urethra B) The length of the urethra C) Sexual intercourse D) Poor personal hygiene E) All of the above are predisposing factors.

C) Gonorrhea.

21) The most common reportable disease in the United States is A) Cystitis. B) Lymphogranuloma venereum. C) Gonorrhea. D) Syphilis. E) Candidiasis.

E) All of the above are potential complications of gonorrhea.

22) Which of the following is NOT a complication of gonorrhea? A) Arthritis B) Pelvic inflammatory disease C) Endocarditis D) Meningitis E) All of the above are potential complications of gonorrhea.

A) Genital herpes

23) Which of the following is the most difficult to treat with chemotherapeutic agents? A) Genital herpes B) Gonorrhea C) Syphilis D) Trichomoniasis E) Leptospirosis

C) Candidiasis.

24) Itching and cheesy discharge are symptoms of A) Gardnerella vaginosis. B) Genital herpes. C) Candidiasis. D) Trichomoniasis. E) Lymphogranuloma venereum.

B) Genital herpes.

25) Recurring vesicles are symptoms of A) Gardnerella vaginosis. B) Genital herpes. C) Candidiasis. D) Trichomoniasis. E) Lymphogranuloma venereum.

D) Trichomoniasis.

26) Leukocytes at the infected site is a symptom of A) Gardnerella vaginosis. B) Genital herpes. C) Candidiasis. D) Trichomoniasis. E) Lymphogranuloma venereum.

E) Lymphogranuloma venereum

27) Which of the following is caused by Chlamydia? A) Gardnerella vaginosis B) Genital herpes C) Candidiasis D) Trichomoniasis E) Lymphogranuloma venereum

D) Pyelonephritis.

28) A positive LE text and 10,000 CFU/ml in urine indicates A) Cystitis. B) Gonorrhea. C) Urethritis. D) Pyelonephritis. E) Genital herpes.

B) Syphilis

29) Which of the following diseases causes a skin rash, hair loss, malaise, and fever? A) Gonorrhea B) Syphilis C) NGU D) Trichomoniasis E) Genital herpes

E) All of the above.

3) Pyelonephritis may result from A) Urethritis. B) Cystitis. C) Ureteritis. D) Systemic infections. E) All of the above.

A) Cystitis.

30) Staphylococcus saprophyticus causes A) Cystitis. B) Pyelonephritis. C) Vaginitis. D) Gonorrhea. E) Syphilis.

C) It is always precancerous.

31) Which one of the following statements about genital warts is false? A) It is transmitted by direct contact. B) It is caused by papillomaviruses. C) It is always precancerous. D) It is treated by removing them. E) All of the above.

B) Cephalosporins.

32) The most common NGU in the United States is treated with A) Penicillin. B) Cephalosporins. C) Acyclovir. D) AZT. E) Doxycycline.

E) It affects men and women equally.

33) Which of the following statements about pelvic inflammatory disease is false? A) It can cause sterility and chronic pain. B) It can be caused by N. gonorrhoeae. C) It can be transmitted sexually. D) It can be caused by C. trachomatis. E) It affects men and women equally.

C) Neisseria.

34) Which one of the following does NOT cause nongonococcal urethritis? A) Chlamydia. B) Mycoplasma. C) Neisseria. D) Ureaplasma. E) All of the above cause NGU.

A) Maternal antibodies offer protection.

35) Infants born to asymptomatic mothers with recurrent genital herpes are less likely to acquire herpesvirus at birth than infants born to newly infected mothers because A) Maternal antibodies offer protection. B) The disease cannot be transmitted to newborns. C) The disease is not communicable. D) Prophylactic antibiotics are administered to the newborn. E) The virus isn't growing.

A) The number of reported cases of gonorrhea last year

36) Which of the following is greater? A) The number of reported cases of gonorrhea last year B) The number of reported cases of AIDS last year C) They are equal.

C) Acyclovir

37) A patient presents with fever and extensive lesions of the labia minora. Her VDRL test was negative. What is the most likely treatment? A) Metronidazole B) Cephalosporins C) Acyclovir D) Miconazole E) No treatment is available.

A) Metronidazole

38) A patient is experiencing profuse greenish yellow, foul-smelling discharge from her vagina. She is complaining of itching and irritation. What is the most likely treatment? A) Metronidazole B) Cephalosporins C) Acyclovir D) Miconazole E) No treatment is available.

B) Mumps virus.

39) A 25-year-old man presented with fever, malaise, and a rash on his chest, arms, and feet. The etiology could be any of the following EXCEPT A) Borrelia. B) Mumps virus. C) Rickettsia. D) Streptococcus. E) Treponema.

D) Opa attaches to CD4+ T lymphocytes

4) All of the following result from N. gonorrhoeae infection. Which one leads to the others? A) Antibody production is stopped B) CD4+ T lymphocytes don't reproduce C) Increased risk of other STIs D) Opa attaches to CD4+ T lymphocytes E) Reinfection by N. gonorrhoeae

31) Which of the following is an example of a metabolic activity that could be used to measure microbial growth? A) standard plate count B) glucose consumption C) direct microscopic count D) turbidity E) MPN

Answer: B

32) Assume you are working for a chemical company and are responsible for growing a yeast culture that produces ethanol. The yeasts are growing well on the maltose medium but are not producing alcohol. What is the most likely explanation? A) The maltose is toxic. B) O2 is in the medium. C) Not enough protein is provided. D) The temperature is too low. E) The temperature is too high.

Answer: B

32) Borrelia is classified as a spirochete because it A) is aerobic. B) possesses an axial filament. C) is a rod. D) is a pathogen. E) is transmitted by ticks.

Answer: B

33) Thiobacillus oxidizes inorganic sulfur compounds and reduces CO2. This bacterium is a A) chemoheterotroph. B) chemoautotroph. C) photoautotroph. D) gammaproteobacteria. E) photoheterotroph.

Answer: B

33) Which of the following would be selective against the tubercle bacillus? A) bacitracin inhibits peptidoglycan synthesis B) ethambutol inhibits mycolic acid synthesis C) streptogramin inhibits protein synthesis D) streptomycin inhibits protein synthesis E) vancomycin inhibits peptidoglycan synthesis

Answer: B

33) You observe a mass of amboeba-like cells that swarm together, form a stalk, and produce spores. This is a(n) A) ascomycete. B) cellular slime mold. C) Euglenozoa. D) tapeworm. E) plasmodial slime mold.

Answer: B

34) An enzyme, citrate synthase, in the Krebs cycle is inhibited by ATP. This is an example of all of the following EXCEPT A) allosteric inhibition. B) competitive inhibition. C) feedback inhibition. D) noncompetitive inhibition.

Answer: B

34) Which microscope is used to see intracellular detail in a living cell? A) fluorescence microscope B) two-photon microscope C) atomic force microscope D) transmission electron microscope E) brightfield microscope

Answer: B

35) Actinomycetes differ from fungi in that actinomycetes A) are chemoheterotrophs. B) lack a membrane-bounded nucleus. C) require light. D) are decomposers. E) cause disease.

Answer: B

35) 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.

Answer: B

35) Lamisil is an allylamine used to treat dermatomycoses. Lamisil's method of action is similar to that of A) polymyxin B. B) azole antibiotics. C) echinocandins. D) griseofulvin. E) bacitracin.

Answer: B

35) Which of the following is involved in resistance to parasitic helminths? A) basophils B) eosinophils C) lymphocytes D) monocytes E) neutrophils

Answer: B

36) In one hospital, Pseudomonas aeruginosa serotype 10 infected the biliary tract of 10 percent of 1300 patients who underwent gastrointestinal endoscopic procedures. After each use, endoscopes were washed with an automatic reprocessor that flushed detergent and glutaraldehyde through the endoscopes, followed by a tap water rinse. P. aeruginosa 10 was not isolated from the detergent, glutaraldehyde, or tap water. What was the source of the infections? A) bacterial cell walls in the water B) a biofilm in the reprocessor C) contaminated disinfectant D) fecal contamination of the bile ducts E) None of the answers is correct.

Answer: B

36) Into which group would you place a photosynthetic cell that lacks a nucleus? A) Animalia B) Bacteria C) Fungi D) Plantae E) Protista

Answer: B

37) An enzyme that makes covalent bonds between nucleotide sequences in DNA is A) RNA polymerase. B) DNA ligase C) DNA helicase. D) transposase. E) DNA polymerase.

Answer: B

37) Antibiotics can lead to septic shock if used to treat A) viral infections. B) gram-negative bacterial infections. C) gram-positive bacterial infections. D) protozoan infections. E) helminth infestations.

Answer: B

37) Bacteria can increase the Earth's temperature by A) generating a great deal of heat in metabolism. B) producing CH4, which is a greenhouse gas. C) using the greenhouse gas CO2. D) providing nutrients for plant growth. E) oxidizing CH4.

Answer: B

37) You discovered a unicellular organism that lacks a nucleus and peptidoglycan. You suspect the organism is in the group A) Animalia. B) Archaea. C) Bacteria. D) Fungi. E) Plantae.

Answer: B

38) Into which group would you place a unicellular organism that has 70S ribosomes and a peptidoglycan cell wall? A) Animalia B) Bacteria C) Fungi D) Plantae E) Protist

Answer: B

38) Oxygen crosses a plasma membrane A) by osmosis. B) through simple diffusion. C) with the help of a nonspecific transporter. D) through facilitated diffusion. E) through porins.

Answer: B

38) Which step in the Gram stain is the critical step in differentiating gram-positive cells from gram-negative cells? A) safranin B) alcohol-acetone C) iodine D) crystal violet

Answer: B

39) 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.

Answer: B

4) Antimicrobial peptides work by A) inhibiting protein synthesis. B) disrupting the plasma membrane. C) complementary base pairing with DNA. D) inhibiting cell-wall synthesis. E) hydrolyzing peptidoglycan.

Answer: B

4) Seventeen patients in ten hospitals had cutaneous infections caused by Rhizopus. In all seventeen patients, Elastoplast bandages were placed over sterile gauze pads to cover wounds. Fourteen of the patients had surgical wounds, two had venous line insertion sites, and one had a bite wound. Lesions present when the bandages were removed ranged from vesiculopustular eruptions to ulcerations and skin necrosis requiring debridement. Fungi are more likely than bacteria to contaminate bandages because they A) are aerobic. B) can tolerate low-moisture conditions. C) prefer a neutral environment (pH 7). D) have a fermentative metabolism. E) cannot tolerate high osmotic pressure.

Answer: B

4) The ID50 is A) a measure of pathogenicity. B) the dose that will cause an infection in 50 percent of the test population. C) the dose that will kill some of the test population. D) the dose that will cause an infection in some of the test population. E) the dose that will kill 50 percent of the test population.

Answer: B

4) What is the outstanding characteristic of the Kingdom Fungi? A) All members are photosynthetic. B) Members absorb dissolved organic matter. C) Members absorb dissolved inorganic matter. D) All members are microscopic. E) All members are macroscopic.

Answer: B

40) The lectin pathway for complement action is initiated by A) mannose on host membranes. B) mannose on the surface of microbes. C) lectins of the microbe. D) gram-negative cell walls. E) gram-positive cell walls.

Answer: B

40) The yeast Candida albicans does not normally cause disease because of A) symbiotic bacteria. B) antagonistic bacteria. C) parasitic bacteria. D) commensal bacteria. E) other fungi.

Answer: B

40) What will happen if a bacterial cell is placed in distilled water with lysozyme? A) The cell will plasmolyze. B) The cell will undergo osmotic lysis. C) Water will leave the cell. D) Lysozyme will diffuse into the cell. E) No change will result; the solution is isotonic.

Answer: B

41) An antibody's Fc region can be bound by A) antibodies. B) macrophages. C) T helper cells. D) B cells. E) CTLs.

Answer: B

41) If a prodromal period exists for a certain disease, it should occur prior to A) incubation. B) illness. C) decline. D) convalescence.

Answer: B

42) Bacteria that cause periodontal disease have adhesins for receptors on streptococci that colonize on teeth. This indicates that A) streptococci get bacterial infections. B) streptococcal colonization is necessary for periodontal disease. C) bacteria that cause periodontal disease adhere to gums and teeth. D) bacteria that cause periodontal disease adhere to teeth. E) streptococci cause periodontal disease.

Answer: B

42) Mycoplasmas differ from other bacteria in that they A) grow inside host cells. B) lack a cell wall. C) are acid-fast. D) are motile. E) are gram-negative.

Answer: B

42) Which of the following is most likely a product of an early gene? A) capsid proteins B) DNA polymerase C) envelope proteins D) spike proteins E) lysozyme

Answer: B

43) Nonpathogenic Vibrio cholerae can acquire the cholera toxin gene by A) phagocytosis. B) transduction. C) conjugation. D) transformation. E) infecting a pathogenic Vibrio cholerae.

Answer: B

43) The release of phosphate-containing detergents into a river would A) kill algae. B) increase algal growth. C) kill bacteria. D) improve the water quality. E) None of the answers is correct.

Answer: B

43) Yeast infections are caused by A) Aspergillus. B) Candida albicans. C) Histoplasma. D) Penicillium. E) Saccharomyces cerevisiae.

Answer: B

44) IL-2, produced by TH cells, A) activates macrophages. B) stimulates TH cell maturation. C) causes phagocytosis. D) activates antigen-presenting cells. E) activates TC cells to CTLs.

Answer: B

44) In response to the presence of endotoxin, phagocytes secrete tumor necrosis factor. This causes A) the disease to subside. B) a decrease in blood pressure. C) a fever. D) a aram-negative infection. E) an increase in red blood cells.

Answer: B

44) The purpose of the ocular lens is to A) improve resolution. B) magnify the image from the objective lens. C) decrease the refractive index. D) increase the light. E) decrease the light.

Answer: B

45) A urease test is used to identify Myobacterium tuberculosis because A) urease is a sign of tuberculosis. B) M. tuberculosis produces urease. C) urea accumulates during tuberculosis. D) some bacteria reduce nitrate ion. E) M. bovis can cause tuberculosis.

Answer: B

45) What contributes to antigenic shift in influenza viruses? A) worldwide distribution of the virus B) a segmented genome C) attachment spikes D) ease of virus transmission E) different virus subtypes

Answer: B

45) Which non-specific defense mechanism is mismatched with its associated body structure or body fluid? A) lysozyme — tears and saliva B) mucociliary escalator — intestines C) very acidic pH— stomach D) keratin and tightly packed cells — skin E) cerumen and sebum — ear

Answer: B

5) Which of the following is NOT utilized to culture viruses? A) laboratory animals B) culture media C) embryonated eggs D) animal cell cultures E) bacterial cultures

Answer: B

6) Which of the following statements about bacteriocins is FALSE? A) The genes coding for them are on plasmids. B) They cause food-poisoning symptoms. C) Nisin is a bacteriocin used as a food preservative. D) They can be used to identify certain bacteria. E) Bacteriocins kill bacteria.

Answer: B

7) A genus can best be defined as A) a taxon composed of families. B) a taxon composed of one or more species and below family. C) a taxon belonging to a species. D) a taxon comprised of classes. E) the most specific taxon.

Answer: B

7) Which of the following have a cell wall? A) protoplasts B) fungi C) L forms D) mycoplasmas E) animal cells

Answer: B

8) A prokaryotic cell may possess each of the following cellular components EXCEPT A) flagella. B) a nucleus. C) ribosomes. D) a cell wall. E) a cell membrane.

Answer: B

8) A viroid is a(n) A) complete, infectious virus particle. B) infectious piece of RNA without a capsid. C) capsid without nucleic acid. D) provirus. E) infectious protein.

Answer: B

8) Pathogenic bacteria isolated from the respiratory or intestinal tracts of humans are A) strict aerobes that grow best in candle jars. B) capnophiles that grow best in carbon dioxide incubators. C) facultative anaerobes that require reducing media for growth. D) strict aerobes that grow best in reducing media. E) capnophiles that prefer highly oxygenated growth conditions.

Answer: B

8) Which of the following definitions is INCORRECT? A) endemic: a disease that is constantly present in a population B) epidemic: a disease that is endemic across the world C) pandemic: a disease that affects a large number of people in the world in a short time D) sporadic: a disease that affects a population occasionally E) incidence: number of new cases of a disease

Answer: B

8) Which of the following does NOT achieve sterilization? A) dry heat B) pasteurization C) autoclave D) supercritical fluids E) ethylene oxide

Answer: B

8) Which of the following statements is TRUE? A) Endospores are for reproduction. B) Endospores allow a cell to survive environmental changes. C) Endospores are easily stained in a Gram stain. D) A cell produces one endospore and keeps growing. E) A cell can produce many endospores.

Answer: B

9) 6H2S + 6CO2 6S0 + glucose A) takes place under aerobic conditions. B) takes place under anaerobic conditions. C) The amount of oxygen does not make any difference.

Answer: B

Situation 14.1 During a six-month period, 239 cases of pneumonia occurred in a town of 300 people. A clinical case was defined as fever ≥39°C lasting >2 days with three or more symptoms (i.e., chills, sweats, severe headache, cough, aching muscles/joints, fatigue, or feeling ill). A laboratory-confirmed case was defined as a positive result for antibodies against Coxiella burnetii. Before the outbreak, 2000 sheep were kept northwest of the town. Of the 20 sheep tested from the flock, 15 were positive for C. burnetii antibodies. Wind blew from the northwest, and rainfall was 0.5 cm compared with 7 to 10 cm during each of the previous three years. 36) Situation 14.1 is an example of A) human reservoirs. B) a zoonosis. C) a nonliving reservoir. D) a vector. E) a focal infection.

Answer: B

1) A commensal bacterium A) does not receive any benefit from its host. B) is beneficial to its host. C) may also be an opportunistic pathogen. D) does not infect its host. E) is beneficial to, and does not infect, its host.

Answer: C

1) A gene is best defined as A) a segment of DNA. B) three nucleotides that code for an amino acid. C) a sequence of nucleotides in DNA that codes for a functional product. D) a sequence of nucleotides in RNA that codes for a functional product. E) a transcribed unit of DNA.

Answer: C

1) Which of the following are found primarily in the intestines of humans? A) gram-negative aerobic rods and cocci B) aerobic, helical bacteria C) facultatively anaerobic gram-negative rods D) gram-positive cocci E) endospore-forming rods

Answer: C

1) Which of the following compounds is NOT an enzyme? A) dehydrogenase B) cellulase C) coenzyme A D) β-galactosidase E) sucrase

Answer: C

1) Which of the following is the best method to sterilize heat-labile solutions? A) dry heat B) autoclave C) membrane filtration D) pasteurization E) freezing

Answer: C

10) Margination refers to A) the adherence of phagocytes to microorganisms. B) the chemotactic response of phagocytes. C) adherence of phagocytes to the lining of blood vessels. D) dilation of blood vessels. E) the movement of phagocytes through walls of blood vessels.

Answer: C

10) The biosafety level (BSL) for a clinical microbiology laboratory working with potentially airborne pathogens, such as tuberculosis bacteria, is A) BSL-1. B) BSL-2. C) BSL-3. D) BSL-4.

Answer: C

10) The rise in herd immunity amongst a population can directly attributed to A) increased use of antibiotics. B) improved handwashing. C) vaccinations. D) antibiotic-resistant microorganisms. E) None of the answers is correct.

Answer: C

10) Which of the following antimicrobial agents has the fewest side effects? A) streptomycin B) tetracycline C) penicillin D) erythromycin E) chloramphenicol

Answer: C

10) Which of the following recognizes antigens displayed on host cells with MHC II? A) TC cell B) B cell C) TH cell D) natural killer cell E) basophil

Answer: C

11) Which of the following drugs does NOT act by competitive inhibition? A) ethambutol B) isoniazid C) streptomycin D) sulfonamide E) trimethoprim

Answer: C

11) Which of the following statements is TRUE? A) All three types of interferons have the same effect on the body. B) Alpha interferon promotes phagocytosis. C) Gamma interferon causes bactericidal activity by macrophages. D) Alpha interferon acts against specific viruses. E) Beta interferon attacks invading viruses.

Answer: C

12) The phylogenetic classification of bacteria is based on A) cell morphology. B) Gram reaction. C) rRNA sequences. D) habitat. E) diseases.

Answer: C

12) Which of the following disinfectants acts by disrupting the plasma membrane? A) soaps B) aldehydes C) bisphenols D) halogens E) heavy metals

Answer: C

12) Which one of the following does NOT contribute to the incidence of nosocomial infections? A) antibiotic resistance B) lapse in aseptic techniques C) gram-negative cell walls D) lack of handwashing E) lack of insect control

Answer: C

13) Siderophores are bacterial proteins that compete with the host's A) antibodies. B) red blood cells. C) iron-transport proteins. D) white blood cells. E) receptors.

Answer: C

14) A persistent infection is one in which A) the virus remains in equilibrium with the host without causing a disease. B) viral replication is unusually slow. C) the disease process occurs gradually over a long period. D) host cells are gradually lysed. E) host cells are transformed.

Answer: C

14) Which of the following pairs is mismatched? A) dissimilatory sulfate-reducing bacteria & produce H2S B) archaea & extremophiles C) chemoautotrophic bacteria & fix atmospheric nitrogen D) actinomycetes & reproduce by fragmentation E) Cytophaga & a gliding, nonfruiting bacterium

Answer: C

14) Which of the following tends to be more complex in a parasitic helminth than in free-living helminths? A) digestive system B) nervous system C) reproductive system D) digestive and nervous systems E) digestive, reproductive, and nervous systems

Answer: C

15) Biochemical oxygen demand is a measure of the A) number of bacteria present in a water sample. B) amount of oxygen present in a water sample. C) amount of organic matter present in a water sample. D) amount of undissolved solid matter present in a water sample. E) amount of nitrogen in a water sample.

Answer: C

15) Classification of organisms into three domains is based on A) the presence of a cell wall. B) the number of cells in the organism. C) cellular organization. D) nutritional requirements. E) cellular proteins.

Answer: C

15) One effect of washing regularly with antibacterial agents is the removal of normal microbiota. This can result in A) body odor. B) fewer diseases. C) increased susceptibility to disease. D) normal microbiota returning immediately. E) no bacterial growth because washing removes their food source.

Answer: C

15) Rickettsias differ from chlamydias in that rickettsias A) are gram-negative. B) are intracellular parasites. C) require an arthropod for transmission. D) form elementary bodies. E) are enterics.

Answer: C

15) The advantage of the pentose phosphate pathway is that it produces all of the following EXCEPT A) precursors for nucleic acids. B) precursors for the synthesis of glucose. C) three ATPs. D) NADPH. E) precursors for the synthesis of amino acids.

Answer: C

15) The antibodies found in mucus, saliva, and tears are A) IgG. B) IgM. C) IgA. D) IgD. E) IgE.

Answer: C

15) This microscope produces an image of a light cell against a dark background; internal structures are NOT visible. A) compound light microscope B) phase-contrast microscope C) darkfield microscope D) fluorescence microscope E) electron microscope

Answer: C

16) A virus measures 100 nm in length. What is its length in μm? A) 10 μm B) 1 μm C) .1 μm D) 0.01 μm E) 0.001 μm

Answer: C

16) According to the operon model, for the synthesis of an inducible enzyme to occur, the A) end-product must not be in excess. B) substrate must bind to the enzyme. C) substrate must bind to the repressor. D) repressor must bind to the operator. E) repressor must not be synthesized.

Answer: C

16) Each of the following provides protection from phagocytic digestion EXCEPT A) M protein. B) capsules. C) formation of phagolysosomes. D) leukocidins. E) biofilms.

Answer: C

16) Lysogeny can result in all of the following EXCEPT A) immunity to reinfection by the same phage. B) acquisition of new characteristics by the host cell. C) immunity to reinfection by any phage. D) specialized transduction. E) phage conversion.

Answer: C

16) Superantigens produce intense immune responses by stimulating lymphocytes to produce A) endotoxins. B) exotoxins. C) cytokines. D) leukocidins. E) interferons.

Answer: C

16) Which of the following is an advantage of the direct microscopic count? A) can readily count organisms that are motile B) can easily distinguish live from dead cells C) requires no incubation time D) sample volume is unknown E) requires a large number of cells

Answer: C

16) Which of the following methods is used to preserve food by slowing the metabolic processes of foodborne microbes? A) lyophilization B) nonionizing radiation C) freezing D) ionizing radiation E) pasteurization

Answer: C

16) Which of the following pairs are mismatched? 1. arthroconidium & formed by fragmentation 2. sporangiospore & formed within hyphae 3. conidiospore & formed in a chain 4. blastoconidium & formed from a bud 5. chlamydoconidium & formed in a sac A) 1 and 2 B) 2 and 3 C) 2 and 5 D) 3 and 4 E) 4 and 5

Answer: C

17) Which of the following is required for composting? A) addition of non-biodegradable materials B) addition of nitrogen and phosphorus sources C) periodic turning or raking of the compost pile D) addition of thermophilic microbes E) constant anaerobic conditions

Answer: C

17) Which of the following structures is NOT found in some prokaryotic cells? A) flagellum B) axial filament C) cilium D) pilus E) peritrichous flagella

Answer: C

17) You have isolated a bacterium that grows in a medium containing only inorganic nutrients. Ammonia is oxidized to a nitrate ion. This bacterium is A) gram-negative. B) using anaerobic respiration. C) a chemoautotroph. D) a photoautotroph E) a photoheterotroph.

Answer: C

18) Helminthic diseases are usually transmitted to humans by A) respiratory route. B) genitourinary route. C) gastrointestinal route. D) vectors. E) aerosols.

Answer: C

18) Which of the following bacteria is gram-positive? A) Pseudomonas B) Salmonella C) Streptococcus D) Bacteroides E) Rickettsia

Answer: C

19) All of the following are characteristic of the Platyhelminthes EXCEPT that they A) are hermaphroditic. B) are dorsoventrally flattened. C) have highly developed digestive and nervous systems. D) can be divided into flukes and tapeworms. E) are multicellular animals.

Answer: C

19) Which of the following is mismatched? A) Ehrlich - "magic bullet" theory B) Fleming - identification of penicillin C) Florey and Chain - identification of Penicillium as the producer of penicillin D) Kirby and Bauer - disc-diffusion method E) None of these is mismatched.

Answer: C

19) Which of the following statements about biological transmission is FALSE? A) The pathogen reproduces in the vector. B) The pathogen may enter the host in the vector's feces. C) Houseflies are an important vector. D) The pathogen may be injected by the bite of the vector. E) The pathogen may require the vector as a host.

Answer: C

19) Which structure acts like an "invisibility cloak" and protects bacteria from being phagocytized? A) slime layer B) fimbriae C) capsule D) cell membrane E) cell wall

Answer: C

2) A drug that inhibits mitosis, such as griseofulvin, would be more effective against A) gram-positive bacteria. B) gram-negative bacteria. C) fungi. D) wall-less bacteria. E) mycobacteria.

Answer: C

2) Each of the following statements concerning the gram-positive cell wall is true EXCEPT A) it maintains the shape of the cell. B) it is sensitive to lysozyme. C) it protects the cell in a hypertonic environment. D) it contains teichoic acids. E) it is sensitive to penicillin.

Answer: C

2) What structure does light pass through after leaving the condenser in a compound light microscope? A) ocular lens B) objective lens C) specimen D) illuminator

Answer: C

2) Which of the following characterizes the Domain Bacteria? A) prokaryotic cells; ether linkages in phospholipids B) eukaryotic cells; ester linkages in phospholipids C) prokaryotic cells; ester linkages in phospholipids D) complex cellular structures E) multicellular

Answer: C

2) Which of the following statements provides the most significant support for the idea that viruses are nonliving chemicals? A) They are not composed of cells. B) They are filterable. C) They cannot reproduce themselves outside a host. D) They cause diseases similar to those caused by chemicals. E) They are chemically simple.

Answer: C

20) Which compound would be the most useful to treat candidiasis? A) uracil B) thymine C) flucytosine D) guanine E) penicillin

Answer: C

20) Which of the following is NOT part of the passive transport process? A) plasma membrane B) transporter proteins C) ATP D) concentration gradient E) aquaporins

Answer: C

21) Most bacteria grow best at pH A) 1. B) 5. C) 7. D) 9. E) 14.

Answer: C

21) Which microscope can be used to visualize DNA or botulinum toxin? A) compound light microscope B) phase-contrast microscope C) scanning tunneling microscope D) confocal microscope E) scanning electron microscope

Answer: C

22) A primary difference between cyanobacteria and purple and green phototrophic bacteria is A) energy source. B) cell wall type. C) electron donor for CO2 reduction. D) cell type. E) color.

Answer: C

22) In bacteria, photosynthetic pigments are found in A) chloroplasts. B) cytoplasm. C) chromatophores. D) mesosomes. E) ribosomes.

Answer: C

22) The encysted larva of the beef tapeworm is called a A) redia. B) cercaria. C) cysticercus. D) metacercaria. E) proglottid.

Answer: C

23) Which of the following arthropods does NOT transmit diseases by sucking blood from a human host? A) lice B) fleas C) houseflies D) mosquitoes E) kissing bugs

Answer: C

24) Phage typing is based on the fact that A) bacteria are destroyed by viruses. B) viruses cause disease. C) bacterial viruses attack only members of a specific species. D) Staphylococcus causes infections. E) phages and bacteria are related.

Answer: C

24) Proof that a microbe could cause disease was provided by A) Pasteur. B) Lister. C) Koch. D) Wasserman. E) Semmelweis.

Answer: C

25) The most conclusive evidence that viruses cause cancers is provided by A) finding oncogenes in viruses. B) the presence of antibodies against viruses in cancer patients. C) cancer following injection of cell-free filtrates. D) treating cancer with antibodies. E) some liver cancer patients having had hepatitis.

Answer: C

25) Which wastewater treatment process is responsible for removal of most of the BOD in sewage? A) anaerobic sludge digestion B) primary sewage treatment C) secondary sewage treatment D) tertiary sewage treatment E) water treatment

Answer: C

25) You have isolated a motile, gram-positive cell with no visible nucleus. You can safely assume that the cell A) has 9 pairs + 2 flagella. B) has a mitochondrion. C) has a cell wall. D) lives in an extreme environment. E) has cilia.

Answer: C

26) Cyanobacteria are a type of A) chemoautotroph. B) chemoheterotroph. C) photoautotroph. D) photoheterotroph.

Answer: C

26) Nucleic acid hybridization is based on the fact that A) the strands of DNA can be separated. B) a chromosome is composed of complementary strands. C) pairing between complementary bases occurs. D) DNA is composed of genes. E) all cells have DNA.

Answer: C

26) Which wastewater treatment process produces BOD-containing effluent used for irrigation? A) anaerobic sludge digestion B) primary sewage treatment C) secondary sewage treatment D) tertiary sewage treatment E) water treatment

Answer: C

27) A definitive host harbors which stage of a parasite? A) miracidium B) cyst C) adult D) larva E) All of the answers are correct.

Answer: C

27) The first step for directly linking a microbe to a specific disease according to Koch's postulates is to A) culture the blood or other body fluid from a diseased animal using nutrient medium. B) inject a sample of blood or other body fluid from a diseased animal into a healthy animal. C) obtain a sample of blood or other body fluid from a diseased animal. D) compare the blood of a sick animal to blood obtained from a healthy animal. E) isolate microbes from the blood of healthy animals.

Answer: C

27) You are performing a Gram stain on gram-negative bacteria and you stop after the decolorizer step. What is the appearance of the bacteria at this point? A) purple B) red C) colorless D) brown

Answer: C

28) Generally, in an infection caused by a DNA-containing virus, the host animal cell supplies all of the following EXCEPT A) RNA polymerase. B) nucleotides. C) DNA polymerase. D) tRNA. E) None of the answers are correct; all of these are supplied by the host animal cell.

Answer: C

28) Microorganisms that catabolize sugars into ethanol and hydrogen gas would most likely be categorized as A) aerobic respirers. B) anaerobic respirers. C) heterolactic fermenters. D) homolactic fermenters. E) alcohol fermenters.

Answer: C

28) The classical pathway for complement activation is initiated by A) lipid-carbohydrate complexes and C3. B) C5C9. C) antigenantibody reactions. D) factors released from phagocytes. E) factors released from damaged tissues.

Answer: C

28) Which of the following does NOT constitute an advantage of using two antibiotics together? A) It can prevent drug resistance. B) It lessens the toxicity of individual drugs. C) Two are always twice as effective as one. D) It allows treatment to be provided prior to diagnosis. E) All of these are advantages of using two antibiotics together.

Answer: C

29) A researcher has performed a prospective study on the disease tetanus. To which specific kind of epidemiological study is this referring? A) analytical B) case control C) descriptive D) experimental E) prodromal

Answer: C

29) Polio is transmitted by ingestion of water contaminated with feces containing polio virus. What portal of entry does polio virus use? A) skin only B) parenteral only C) mucous membranes only D) skin and parenteral E) skin, parenteral, and mucous membranes

Answer: C

29) Which type of stain is most useful in helping clinicians to decide which antibiotic to prescribe for a bacterial infection? A) negative stain B) simple stain C) Gram stain D) endospore stain E) flagella stain

Answer: C

3) 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.

Answer: C

3) Which of the following chemical agents is used for sterilization? A) alcohol B) phenolics C) ethylene oxide D) chlorine E) soap

Answer: C

3) Which of the following statements best describes what happens when a bacterial cell is placed in a solution containing 5 percent NaCl? A) Sucrose will move into the cell from a higher to a lower concentration. B) The cell will undergo osmotic lysis. C) Water will move out of the cell. D) Water will move into the cell. E) No change will result; the solution is isotonic.

Answer: C

30) Conjugation differs from reproduction because conjugation A) replicates DNA. B) transfers DNA vertically, to new cells. C) transfers DNA horizontally, to cells in the same generation. D) transcribes DNA to RNA. E) copies RNA to make DNA.

Answer: C

30) Neutrophils with defective lysosomes are unable to A) undergo chemotaxis. B) migrate. C) produce toxic oxygen products. D) attach to microorganisms and other foreign material. E) engulf microorganisms and other foreign material.

Answer: C

30) The life cycle of the fish tapeworm is similar to that of the beef tapeworm. Which of the following is the most effective preventive measure? A) salting fish before eating B) refrigerating stored fish C) cooking fish before eating D) wearing gloves while handling fish E) not swimming in fish-infested waters

Answer: C

30) Which of the following pairs is mismatched? A) confocal microscope —produces a three-dimensional image B) darkfield microscope —uses visible light C) fluorescence microscope —uses a fluorescent light D) scanning electron microscope —produces a three-dimensional image E) scanning tunneling microscope —allows visualization of atoms

Answer: C

30) Zoogloea form flocculent masses in A) anaerobic sludge digestion. B) primary sewage treatment. C) secondary sewage treatment. D) tertiary sewage treatment. E) water treatment.

Answer: C

31) A disease in which the causative agent remains inactive for a time before producing symptoms is referred to as A) subacute. B) subclinical. C) latent. D) zoonotic. E) acute.

Answer: C

31) Cholera toxin polypeptide A binds to surface gangliosides on target cells. If the gangliosides were removed, A) polypeptide A would bind to target cells. B) polypeptide A would enter the cells. C) polypeptide B would not be able to enter the cells. D) Vibrio would not produce cholera toxin. E) Vibrio would bind to target cells.

Answer: C

31) Drinking water supplies are routinely tested for the presence of A) Giardia. B) Cryptosporidium. C) fecal coliforms. D) fecal viruses. E) Vibrio.

Answer: C

31) Innate immunity includes all of the following EXCEPT A) phagocytosis. B) inflammation. C) production of antibody. D) production of interferon. E) activation of complement.

Answer: C

31) Viruses that utilize reverse transcriptase belong to the virus families A) Retroviridae and Picornaviridae. B) Herpesviridae and Retroviridae. C) Hepadnaviridae and Retroviridae. D) Herpesviridae and Poxviridae. E) Rhabdoviridae and Herpesviridae.

Answer: C

31) Which of the following is the most effective control for malaria? A) vaccination B) treating patients C) eliminate Anopheles D) eliminate the intermediate host E) None of these is an effective control.

Answer: C

31) You have isolated a gram-positive rod. What should you do next? A) Gram stain B) lactose fermentation C) endospore stain D) flagella stain E) enterotube

Answer: C

32) A needlestick is an example of A) direct contact. B) droplet transmission. C) fomite. D) vector. E) vehicle transmission.

Answer: C

32) Aerobic respiration occurs in A) anaerobic sludge digestion. B) primary sewage treatment. C) secondary sewage treatment. D) tertiary sewage treatment. E) water treatment.

Answer: C

32) Bacteria such as E. coli and Salmonella produce invasins that bind host cells, thus causing the cells to A) release TNF. B) produce iron-binding proteins. C) engulf the bacteria. D) destroy the bacteria. E) release cytokines.

Answer: C

32) DNA made from an RNA template will be incorporated into the virus capsid of A) Retroviridae. B) Herpesviridae. C) Hepadnaviridae. D) bacteriophage families. E) influenzavirus.

Answer: C

33) Activation of C5C9 results in A) activation of C3. B) fixation of complement. C) lysis of microbial cells. D) phagocytosis. E) inflammation.

Answer: C

33) The first antibiotic to be utilized was A) salvarsan. B) vancomycin. C) penicillin. D) sulfonamides. E) quinine.

Answer: C

33) The presence of which of the following indicates a current infection rather than a previous infection or vaccination? A) IgA B) IgG C) IgM D) IgD E) IgE

Answer: C

33) Three cells with generation times of 60 minutes are inoculated into a culture medium. How many cells are there after 5 hours? A) 900 B) 180 C) 96 D) 32 E) 15

Answer: C

34) In the presence of penicillin, a cell dies because A) it lacks a cell wall. B) it plasmolyzes. C) it undergoes lysis. D) it lacks a cell membrane. E) its contents leak out.

Answer: C

34) Where are phospholipids most likely found in a prokaryotic cell? A) flagella B) around organelles C) the plasma membrane D) ribosomes E) the plasma membrane and around organelles

Answer: C

34) Who was the first scientist to pursue a "magic bullet" that could be used to treat infectious disease? A) Jenner B) Pasteur C) Ehrlich D) Lister E) Semmelweis

Answer: C

35) If a cell is starved for ATP, which of the following pathways would most likely be shut down? A) Kreb's cycle B) glycolysis C) pentose phosphate pathway D) Krebs cycle and glycolysis

Answer: C

35) Which of the following do NOT fix atmospheric nitrogen? A) cyanobacteria B) lichens C) mycorrhizae D) Frankia E) Azotobacter

Answer: C

36) Niclosamide prevents ATP generation in mitochondria. You would expect this drug to be effective against A) gram-negative bacteria. B) gram-positive bacteria. C) helminths. D) Mycobacterium tuberculosis. E) viruses.

Answer: C

36) Which of the following is NOT found in mitochondria and prokaryotes? A) circular chromosome B) 70S ribosomes C) cell wall D) binary fission E) ATP-generating mechanism

Answer: C

36) Which of the following is mismatched? A) CO2 + 4H2 → CH4 + 2H2O Methane-producing bacteria B) Fe2+ → Fe3+ Thiobacillus ferrooxidans C) 6CO2 + 6H2O → C6H12O6 + 6O2 Clostridium D) N2 + 6H+ → 2NH3 Beijerinckia E) SO42- + 10H+ → H2S + 4H2O Desulfovibrio

Answer: C

36) Which of the following organisms is photoautotrophic protozoan? A) oomycote B) cellular slime mold C) Euglena D) Phytophthora E) plasmodial slime mold

Answer: C

37) Assume you stain Bacillus by applying malachite green with heat and then counterstaining with safranin. Through the microscope, the green structures are A) cell walls. B) capsules. C) endospores. D) flagella. E) The answer cannot be determined.

Answer: C

37) The etiologic agent of the disease in Situation 14.1 is A) sheep. B) soil. C) Coxiella burnetii. D) pneumonia. E) wind.

Answer: C

38) A bacterial culture grown in a glucose-peptide medium causes the pH to increase. The bacteria are most likely A) fermenting the glucose. B) oxidizing the glucose. C) using the peptides. D) not growing.

Answer: C

38) At a minimum, the human immune system is capable of recognizing approximately how many different antigens? A) 105 B) 1010 C) 1015 D) 1020 E) 1025

Answer: C

38) 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.

Answer: C

39) Assume you inoculated 100 cells into 100 ml of nutrient broth. You then inoculated 100 cells of the same species into 200 ml of nutrient broth. After incubation for 24 hours, you should have A) more cells in the 100 ml. B) more cells in the 200 ml. C) the same number of cells in both. D) The answer cannot be determined based on the information provided.

Answer: C

39) Caulobacter are different from most bacteria in that they A) are gram-negative. B) are gram-positive. C) have stalks. D) lack cell walls. E) are motile.

Answer: C

39) Which one of the following processes in sewage treatment requires bacterial metabolism? A) chlorination B) primary treatment C) removal of BOD D) sedimentation E) None of the answers is correct.

Answer: C

4) All of the following are true of mycorrhizae EXCEPT A) they are fungi that form beneficial relationships with plants. B) an example is the food delicacy truffles. C) the vesicular-arbuscular mycorrhizae are a type of ectomycorrhizae. D) they enable plants to absorb soil nutrients. E) ectomycorrhizae form a mantle over plant roots.

Answer: C

4) DNA is constructed of A) a single strand of nucleotides with internal hydrogen bonding. B) two complementary strands of nucleotides bonded A—C and G—T. C) two strands of nucleotides running antiparallel. D) two strands of identical nucleotides with hydrogen bonds between them. E) None of the answers is correct.

Answer: C

4) Which of the following exhibits the highest phagocytic activity? A) neutrophils B) erythrocytes C) macrophages D) basophils E) eosinophils

Answer: C

4) Which of the following places the steps of the Gram stain in the correct order? 1-Alcohol-acetone 2-Crystal violet 3-Safranin 4-Iodine A) 1-2-3-4 B) 2-1-4-3 C) 2-4-1-3 D) 4-3-2-1 E) 1-3-2-4

Answer: C

4) Which of the following statements about anaerobic respiration is FALSE? A) It yields lower amounts of ATP when compared to aerobic respiration. B) The complete Kreb's cycle is utilized. C) It involves the reduction of an organic final electron acceptor. D) It generates ATP. E) It requires cytochromes.

Answer: C

4) Which of the following substances is used for surgical hand scrubs? A) phenol B) chlorine bleach C) chlorhexidine D) soap E) glutaraldehyde

Answer: C

40) 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.

Answer: C

40) Oncogenic viruses A) cause acute infections. B) are genetically unstable. C) cause tumors to develop. D) are lytic viruses that kill the host cell. E) have no effect on the host cell.

Answer: C

40) The source of nutrients in nutrient agar is A) agar. B) nutrient. C) peptone and beef extract. D) peptone and NaCl. E) agar and NaCl.

Answer: C

41) How do spirochetes and spirilla differ? A) Spirochetes do not have a cell wall but spirilla do. B) Spirilla are found in chains of cells whereas spirochetes exist as individual cells. C) Spirilla have an external flagella but spirochetes have axial filaments. D) Spirochetes have a rigid, corkscrew shape while spirilla are helical and more flexible. E) Spirochetes and spirilla are basically the same organisms and the terms can be used interchangeably.

Answer: C

41) 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.

Answer: C

42) A Treg cell deficiency could result in A) increased number of viral infections. B) increased number of bacterial infections. C) autoimmunity. D) increased severity of bacterial infections. E) transplant rejection.

Answer: C

42) In the early 1900s, cities such as Philadelphia reduced the incidence of typhoid fever by A) isolating human carriers. B) using tertiary water treatment systems. C) filtering municipal drinking water through sand-bed filters. D) requiring residents to boil drinking water. E) mass vaccination of residents.

Answer: C

42) Recombinant DNA technology has become an increasingly important part of our life. It is used for all of the following EXCEPT A) vaccine production. B) enhancing food longevity. C) synthesis of water. D) drug production. E) increasing the nutritional value of food.

Answer: C

42) The preservation of beef jerky from microbial growth relies on which method of microbial control? A) filtration B) lyophilization C) desiccation D) ionizing radiation E) supercritical CO2

Answer: C

42) The resolution of a microscope can be improved by changing the A) condenser. B) fine adjustment. C) wavelength of light. D) diaphragm. E) coarse adjustment.

Answer: C

42) Which one of the following pairs is mismatched? A) metachromatic granules - phosphate storage B) lipid inclusions - energy reserve C) ribosomes - protein storage D) sulfur granules - energy reserve E) gas vacuoles - flotation

Answer: C

43) A student is looking at a bacterial specimen using the oil immersion lens, but has forgotten to put immersion oil on the slide. The specimen will appear A) smaller than it would if immersion oil was used. B) larger than it would if immersion oil was used. C) somewhat fuzzy and have poor resolution. D) the same as it would if the immersion oil was used. E) to have no color.

Answer: C

43) Most RNA viruses carry which of the following enzymes? A) DNA-dependent DNA polymerase B) lysozyme C) RNA-dependent RNA polymerase D) reverse transcriptase E) ATP synthase

Answer: C

43) Pseudomonas bacteria colonized the bile duct of a patient following his liver transplant surgery. This is an example of a A) communicable disease. B) latent infection. C) nosocomial infection. D) sporadic disease. E) None of the answers is correct.

Answer: C

43) Which enzyme catalyzes the reaction: H2O2 + 2H+ → 2H2O? A) catalase B) oxidase C) peroxidase D) superoxide dismutase

Answer: C

43) Which of the following statements about the classical pathway of complement activation is FALSE? A) C1 is the first protein activated in the classical pathway. B) The C1 protein complex is initiated by antigenantibody complexes. C) C3 is not involved in the classical pathway. D) Cleaved fragments of some of the proteins act to increase inflammation. E) C3b causes opsonization.

Answer: C

44) Assume the two E.coli strains shown below are allowed to conjugate. Hfr: pro+, arg+, his+, lys+, met+, ampicillin-sensitive F: pro-, arg-, his-, lys-, met-, ampicillin-resistant What supplements would you add to glucose minimal salts agar to select for a recombinant cell that is lys+, arg+, amp-resistant? A) ampicillin, lysine, arginine B) lysine, arginine C) ampicillin, proline, histidine, methionine D) proline, histidine, methionine E) ampicillin, prolein, histidine, lysine

Answer: C

44) Lysozyme and the antibiotic penicillin have similar mechanisms of action in that they both cause damage to the bacterial A) cell membrane. B) capsule. C) cell wall. D) DNA. E) ribosomes.

Answer: C

44) The following steps occur during biosynthesis of a + strand RNA virus. What is the third step? A) attachment B) penetration and uncoating C) synthesis of - strand RNA D) synthesis of + strand RNA E) synthesis of viral proteins

Answer: C

44) Which of the following characteristics indicates that two organisms are closely related? A) Both are cocci. B) Both ferment lactose. C) Both of their DNA can hybridize. D) Both normally live in clams. E) Both are motile.

Answer: C

45) Development of emerging infectious disease can be a result of all of the following EXCEPT A) microbial mutation. B) modern transportation. C) use of genetically modified foods. D) changes in the environment. E) overuse of antibiotics.

Answer: C

45) Patients developed inflammation a few hours following eye surgery. Instruments and solutions were sterile, and the Limulus assay was positive. The patients' inflammation was due to A) bacterial infection. B) viral infection. C) endotoxin. D) exotoxin. E) The answer cannot be determined based on the information provided.

Answer: C

45) The DNA found in most bacterial cells A) is surrounded by a nuclear membrane. B) utilizes histones for chromosomal packaging. C) is circular in structure. D) is linear in structure. E) is found in multiple copies.

Answer: C

45) Which of the following statements is FALSE? A) Antimicrobial therapy for hemodialysis-associated infections increases antibiotic resistance. B) S. aureus is differentiated from other mannitol+ cocci by the coagulase test. C) The M in MRSA stands for mannitol. D) The USA100 strain accounts for most hospital-acquired MRSA. E) The USA300 strain accounts for most community-acquired MRSA.

Answer: C

5) By which of the following mechanisms can a cell transport a substance from a lower to a higher concentration? A) simple diffusion B) facilitated diffusion C) active transport D) extracellular enzymes E) aquaporins

Answer: C

5) Newborns' immunity due to the transfer of antibodies across the placenta is an example of A) innate immunity. B) naturally acquired active immunity. C) naturally acquired passive immunity. D) artificially acquired active immunity. E) artificially acquired passive immunity.

Answer: C

5) Staphylococcus and Streptococcus can be easily differentiated in a laboratory by which one of the following? A) cell shape B) Gram stain reaction C) growth in high salt concentrations D) ability to cause disease E) glucose fermentation

Answer: C

5) Which of the following pairs is mismatched? A) alcohol-acetone — decolorizer B) crystal violet — basic dye C) safranin — acid dye D) iodine — mordant E) carbolfuchsin — basic dye

Answer: C

6) A differential cell count is used to determine each of the following EXCEPT A) the total number of white blood cells. B) the numbers of each type of white blood cell. C) the number of red blood cells. D) leukocytosis. E) leukopenia.

Answer: C

6) Which of the following antibiotics is NOT bactericidal? A) aminoglycosides B) cephalosporins C) polyenes D) rifampins E) penicillin

Answer: C

6) Which of the following genera is an anaerobic gram-negative rod? A) Escherichia B) Staphylococcus C) Bacteroides D) Treponema E) Neisseria

Answer: C

6) Which of the following is NOT true regarding the acid-fast stain? A) It is used to identify members of the genus Mycobacterium. B) Acid-fast cells retain the primary dye after treatment with acid-alcohol. C) If cells are acid-fast, they are gram-negative. D) Acid-fast cells appear red in a completed acid-fast stain. E) Non-acid-fast microbes appear blue in a completed acid-fast stain.

Answer: C

6) Which of the following statements about the members of the Kingdom Animalia is FALSE? A) They are multicellular. B) They are composed of eukaryotic cells. C) They undergo photosynthesis. D) They ingest nutrients through a mouth. E) They are heterotrophs.

Answer: C

7) Biological transmission differs from mechanical transmission in that biological transmission A) requires an arthropod. B) involves fomites. C) involves specific diseases. D) requires direct contact. E) works only with noncommunicable diseases.

Answer: C

7) In freshwater lakes and ponds, the majority of photosynthetic microbes are located in the ________ zone(s). A) benthic B) profundal C) limnetic D) littoral E) benthic and profundal

Answer: C

7) In the name Staphylococcus aureus, aureus is the A) genus. B) domain name. C) specific name. D) kingdom. E) family name.

Answer: C

7) The complement protein cascade is the same for the classical pathway, alternative pathway, and lectin pathway beginning with the activation of A) C1. B) C2. C) C3. D) C5. E) C6.

Answer: C

7) 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.

Answer: C

8) All of the following increase blood vessel permeability EXCEPT A) kinins. B) prostaglandins. C) lysozymes. D) histamine. E) leukotrienes.

Answer: C

8) 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.

Answer: C

8) Which of the following places the steps in the correct sequence? 1-Staining 2-Making a smear 3-Fixing A) 1-2-3 B) 3-2-1 C) 2-3-1 D) 1-3-2 E) The order is unimportant.

Answer: C

9) A child falls and suffers a deep cut on her leg. The cut went through her skin and she is bleeding. Which of the following defense mechanisms will participate in eliminating contaminating microbes? A) mucociliary escalator B) normal skin flora C) phagocytosis in the inflammatory response D) acidic skin secretions E) lysozyme

Answer: C

9) Focal infections initially start out as A) sepsis. B) bacteremia. C) local infections. D) septicemia. E) systemic infections.

Answer: C

1) How do all viruses differ from bacteria? A) Viruses are filterable. B) Viruses are obligate intracellular parasites. C) Viruses do not have any nucleic acid. D) Viruses are not composed of cells. E) Viruses do not reproduce.

Answer: D

1) What type of immunity results from vaccination? A) innate immunity B) naturally acquired active immunity C) naturally acquired passive immunity D) artificially acquired active immunity E) artificially acquired passive immunity

Answer: D

1) Which of the following is NOT equal to 1 mm? A) 0.001 m B) 10 6 nm C) 0.1 cm D) 100 μm E) 10-3 m

Answer: D

1) Which of the following statements about archaea is FALSE? A) They are prokaryotes. B) They lack peptidoglycan in their cell walls. C) Some are thermoacidophiles; others are extreme halophiles. D) They evolved before bacteria. E) Some produce methane from carbon dioxide and hydrogen.

Answer: D

10) Biochemical tests are used to determine A) staining characteristics. B) amino acid sequences. C) nucleic acid-base composition. D) enzymatic activities. E) All of the answers are correct.

Answer: D

10) Which of the following requires aerobic conditions? A) nitrogen fixation B) sludge digestion C) primary sewage treatment D) secondary sewage treatment E) water treatment

Answer: D

11) A clear area against a confluent "lawn" of bacteria is called a A) phage. B) pock. C) cell lysis. D) plaque. E) rash.

Answer: D

11) A sample of milk is tested for its bacterial content in a plate count assay. A one-milliliter sample of the milk is diluted in a 1:10 dilution series. One milliliter of the third dilution tube is plated in a pour plate. After incubation, the plate has 54 colonies, indicating that the original milk sample contained A) 54 cells. B) 540 cells. C) 5400 cells. D) 54,000 cells. E) 540,000 cells.

Answer: D

11) Application of heat to living cells can result in all of the following EXCEPT A) breaking of hydrogen bonds. B) alteration of membrane permeability. C) denaturation of enzymes. D) decreased thermal death time. E) damage to nucleic acids.

Answer: D

11) Koch observed Bacillus anthracis multiplying in the blood of cattle. What is this condition called? A) bacteremia B) focal infection C) local infection D) septicemia E) systemic infection

Answer: D

11) 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

Answer: D

12) 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.

Answer: D

12) Continuous cell lines differ from primary cell lines in that A) viruses can be grown in continuous cell lines. B) continuous cell lines always have to be re-isolated from animal tissues. C) continuous cell lines are derived from primary cell lines. D) continuous cell lines can be maintained through an indefinite number of generations. E) continuous cell lines are from human embryos.

Answer: D

12) What stage of sewage treatment produces methane? A) primary treatment B) secondary treatment C) tertiary treatment D) sludge digestion E) None of the stages of sewage treatment produce methane.

Answer: D

12) Which of the following statements about substrate-level phosphorylation is FALSE? A) It involves the direct transfer of a high-energy phosphate group from an intermediate metabolic compound to ADP. B) No final electron acceptor is required. C) It occurs in glycolysis. D) The oxidation of intermediate metabolic compounds releases energy that is used to generate ATP. E) It occurs in the Krebs cycle.

Answer: D

13) Salts and sugars work to preserve foods by creating a A) depletion of nutrients. B) hypotonic environment. C) lower osmotic pressure. D) hypertonic environment. E) lower pH.

Answer: D

13) Transient microbiota differ from normal microbiota in that transient microbiota A) cause diseases. B) are found in a certain location on the host. C) are always acquired by direct contact. D) are present for a relatively short time. E) never cause disease.

Answer: D

13) Which of the following is NOT a characteristic of cellular immunity? A) The cells originate in bone marrow. B) Cells are processed in the thymus gland. C) It can inhibit the immune response. D) B cells make antibodies. E) T cells react with antigens.

Answer: D

13) Which of the following is necessary for replication of a prion? A) DNA B) DNA polymerase C) lysozyme D) PrPSc E) RNA

Answer: D

13) Which of the following statements about photophosphorylation is FALSE? A) Light liberates an electron from chlorophyll. B) The oxidation of carrier molecules releases energy. C) Energy from oxidation reactions is used to generate ATP from ADP. D) It requires CO2. E) It occurs in photosynthesizing cells.

Answer: D

13) Which of the following statements is a reason for NOT classifying viruses in one of three domains rather than in a fourth domain? A) Some viruses can incorporate their genome into a host's genome. B) Viruses direct anabolic pathways of host cells. C) Viruses are obligate parasites. D) Viruses are not composed of cells. E) All of the answers are correct.

Answer: D

14) 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.

Answer: D

14) Which of the following statements regarding a bacterium that is R+ is FALSE? A) It possesses a plasmid. B) R+ can be transferred to a cell of the same species. C) It is resistant to certain drugs and heavy metals. D) It is F+. E) R+ can be transferred to a different species.

Answer: D

15) All of the following are examples of entry via the parenteral route EXCEPT A) injection. B) bite. C) surgery. D) hair follicle. E) skin cut.

Answer: D

15) Fossil evidence indicates that prokaryotic cells first existed on the Earth A) 350 years ago. B) 3500 years ago. C) 3500 years ago. D) 3.5 billion years ago. E) 3.5 × 1012 years ago.

Answer: D

15) Normal microbiota provide protection from infection in each of the following ways EXCEPT A) they produce antibacterial chemicals. B) they compete with pathogens for nutrients. C) they make the chemical environment unsuitable for nonresident bacteria. D) they produce lysozyme. E) they change the pH of the environment.

Answer: D

15) The initial effect of ionizing radiation on a cell is that it causes A) DNA to break. B) bonding between adjacent thymines. C) base substitutions. D) the formation of highly reactive ions. E) the cells to get hot.

Answer: D

15) Which of the following statements is FALSE? A) Fungi produce sexual spores. B) Fungi produce asexual spores. C) Fungal spores are used in identification of fungi. D) Fungal spores are highly resistant to heat and chemical agents. E) Fungal spores are for asexual or sexual reproduction.

Answer: D

16) Requirements for X and V factors are used to identify A) Staphylococcus. B) Escherichia. C) Neisseria. D) Haemophilus. E) Pseudomonas.

Answer: D

16) The antibodies found on the surface of B cells, and which always exist as monomers, are A) IgG. B) IgM. C) IgA. D) IgD. E) IgE.

Answer: D

16) Which of the following statements about beta oxidation is FALSE? A) It is a method of catabolizing fatty acids. B) It involves the formation of 2-carbon units. C) It involves the formation of acetyl-CoA. D) It is a step in glycolysis. E) It is used in petroleum degradation.

Answer: D

16) Which of the following statements about gram-negative cell walls is FALSE? A) They protect the cell in a hypotonic environment. B) They have an extra outer layer composed of lipoproteins, lipopolysaccharides, and phospholipids. C) They are toxic to humans. D) They are sensitive to penicillin. E) Their Gram reaction is due to the outer membrane.

Answer: D

17) Most bacteria reproduce by A) aerial hyphae. B) fragmentation. C) mitosis. D) binary fission. E) budding.

Answer: D

17) Synthesis of a repressible enzyme is stopped by the A) allosteric transition. B) substrate binding to the repressor. C) corepressor binding to the operator. D) corepressor-repressor complex binding to the operator. E) end product binding to the promoter.

Answer: D

17) Which of the following is NOT a communicable diseases? A) malaria B) AIDS C) tuberculosis D) tetanus E) typhoid fever

Answer: D

17) Which of the following is NOT useful for observing living cells? A) phase-contrast microscope B) darkfield microscope C) scanning acoustic microscope D) scanning electron microscope E) brightfield microscope

Answer: D

18) Thirty-six colonies grew in nutrient agar from 1.0 ml of undiluted sample in a standard plate count. How many cells were in the original sample? A) 4 B) 9 C) 18 D) 36 E) 72

Answer: D

19) Which of the following is NOT necessary for respiration? A) cytochromes B) flavoproteins C) a source of electrons D) oxygen E) quinones

Answer: D

19) Which of the following treatments is the most effective for controlling microbial growth? A) 63°C for 30 minutes B) 72°C for 15 seconds C) 140°C for 4 seconds D) They are equivalent treatments. E) None of the answers is correct.

Answer: D

2) All of the following protect the skin and mucous membranes from infection EXCEPT A) multiple layers of cells. B) tears. C) saliva. D) HCl. E) the "ciliary escalator."

Answer: D

2) Each of the following organisms would be considered a microbe EXCEPT A) yeast. B) protozoan. C) bacterium. D) mushroom. E) virus.

Answer: D

2) Which of the following statements about helminths is FALSE? A) They are heterotrophic. B) They are multicellular animals. C) They have eukaryotic cells. D) All are parasites. E) Some have male and female reproductive organs in one animal.

Answer: D

20) If you were setting up an experiment to disprove spontaneous generation in a liquid medium, which of the following would be essential to the experiment? A) supplying the liquid with nutrients B) starting with a liquid that contains microorganisms C) adding antibiotics to the liquid D) using a sterile liquid and eliminating exposure to microorganisms E) adding carbon dioxide to the liquid

Answer: D

20) Phagocytes utilize all of the following to optimize interaction with microorganisms EXCEPT A) trapping a bacterium against a rough surface. B) opsonization. C) chemotaxis. D) lysozyme. E) complement.

Answer: D

20) Which one of the following would you predict is an allosteric inhibitor of the Krebs cycle enzyme, α-ketoglutarate dehydrogenase? A) citric acid B) α-ketoglutaric acid C) NAD+ D) NADH E) ADP

Answer: D

21) Bacteria and Archaea are similar in which of the following? A) peptidoglycan cell walls B) methionine as the start signal for protein synthesis C) sensitivity to antibiotics D) considered prokaryotic cells E) plasma membrane ester linkage

Answer: D

21) In green and purple bacteria, electrons to reduce CO2 can come from A) CO2. B) H2O. C) C6H12O6. D) H2S. E) chlorophyll.

Answer: D

21) The damage caused by ultraviolet radiation is A) never repaired. B) repaired during transcription. C) repaired during translation. D) cut out and replaced. E) repaired by DNA replication.

Answer: D

22) Which microscope is used to observe a specimen that emits light when illuminated with an ultraviolet light? A) compound light microscope B) phase-contrast microscope C) darkfield microscope D) fluorescence microscope E) electron microscope

Answer: D

22) 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.

Answer: D

23) A culture medium on which only gram-positive organisms grow and a yellow halo surrounds Staphylococcus aureus colonies is called a(n) A) selective medium. B) differential medium. C) enrichment culture. D) selective and differential medium. E) differential and enrichment culture.

Answer: D

23) Assume you have isolated an unknown virus. This virus has a single, positive sense strand of RNA, and possesses an envelope. To which group does it most likely belong? A) herpesvirus B) picornavirus C) retrovirus D) togavirus E) papovavirus

Answer: D

23) The difference between simple diffusion and facilitated diffusion is that facilitated diffusion A) moves materials from a higher to a lower concentration. B) moves materials from a lower to a higher concentration. C) requires ATP. D) requires transporter proteins. E) does not require ATP.

Answer: D

23) Which microscope is most useful for visualizing a biofilm? A) compound light microscope B) phase-contrast microscope C) fluorescence microscope D) scanning acoustic microscope E) transmission electron microscope

Answer: D

24) Which of the following is an assimilation process? A) Thiobacillus: H2S → S0 B) Desulfovibrio: SO42- → H2S C) Proteus: Amino acids → H2S D) Redwood tree: SO42- → Amino acids E) Photosynthetic bacteria: H2S → S0

Answer: D

24) Which of the following statements about algae is FALSE? A) They use light as their energy source. B) They use CO2 as their carbon source. C) They produce oxygen from hydrolysis of water. D) All are unicellular. E) Some are capable of sexual reproduction.

Answer: D

24) Which of the following statements is FALSE? A) Fluoroquinolone inhibits DNA synthesis. B) Acyclovir inhibits DNA synthesis. C) Amantadine inhibits the release of viral nucleic acid. D) Interferon inhibits glycolysis. E) Azoles inhibit plasma membrane synthesis.

Answer: D

24) Which of the following statements is FALSE? A) The variable region of a heavy chain binds with antigen. B) The variable region of a light chain binds with antigen. C) The Fc region attaches to a host cell. D) The constant region of a heavy chain is the same for all antibodies. E) All of the answers are correct.

Answer: D

25) Below are paired items referring to the heartworm Dirofilaria immitis. Which of the pairs is mismatched? A) dog definitive host B) dog sexual reproduction C) mosquito vector D) mosquito definitive host E) None of the pairs is mismatched.

Answer: D

25) 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.

Answer: D

25) Which of the following has bacteriochlorophylls and uses alcohols for carbon? A) chemoautotroph B) chemoheterotroph C) photoautotroph D) photoheterotroph

Answer: D

26) Fimbriae and pili differ in that A) there are only one or two pili per cell. B) pili are used for motility. C) pili are used to transfer DNA. D) pili are used for transfer of DNA and motility. E) pili are used for attachment to surfaces.

Answer: D

26) Which of the following WBCs are NOT lymphocytes? A) cytotoxic T cells B) helper T cells C) NK cells D) M cells E) B cells

Answer: D

26) Which of the following statements about M protein is FALSE? A) It is found on Streptococcus pyogenes. B) It is found on fimbriae. C) It is heat- and acid-resistant. D) It is readily digested by phagocytes. E) It is a protein.

Answer: D

27) Bacteriophage replication differs from animal virus replication because only bacteriophage replication involves A) adsorption to specific receptors. B) assembly of viral components. C) replication of viral nucleic acid. D) injection of naked nucleic acid into the host cell. E) lysis of the host cell.

Answer: D

27) 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.

Answer: D

27) The following events elicit an antibody response. What is the third step? A) Antigen-digest goes to surface of APC. B) APC phagocytizes antigen. C) B cell is activated. D) TH cell recognizes antigen-digest and MHC II. E) TH cell produces cytokines.

Answer: D

27) Which of the following is the best reason to classify Streptococcus in the Lactobacillales? A) Gram reaction B) morphology C) fermentation of lactose D) rRNA sequences E) found in dairy products

Answer: D

27) Which of the following statements about drug resistance is FALSE? A) It may be carried on a plasmid. B) It may be transferred from one bacterium to another during conjugation. C) It may be due to enzymes that degrade some antibiotics. D) It is found only in gram-negative bacteria. E) It may be due to increased uptake of a drug.

Answer: D

28) All of the following statements are reasons why fluorescent in situ hybridization (FISH) has become a valuable tool for environmental microbiologists EXCEPT A) it allows for detection of uncultured microbes. B) it demonstrates the diversity of microbes in an environment. C) it allows observation of microbes in their natural environment in association with other microbes. D) it allows one to obtain pure cultures of microbes. E) All of the answers are correct.

Answer: D

28) Streptomyces differs from Actinomyces because Streptomyces A) makes antibiotics. B) produces conidia. C) forms filaments. D) is a strict aerobe. E) is a bacterium.

Answer: D

28) What do tapeworms eat? A) intestinal bacteria B) host tissues C) red blood cells D) intestinal contents E) plant matter

Answer: D

28) Which of the following is NOT a direct method to measure microbial growth? A) direct microscopic count B) standard plate count C) filtration D) metabolic activity E) most probable number (MPN)

Answer: D

29) All of the following bacteria are gram-positive. Which does NOT belong with the others? A) Actinomyces B) Bacillus C) Corynebacterium D) Listeria E) Mycobacterium

Answer: D

29) Which of the following statements regarding metabolism is FALSE? A) Heat may be released in both anabolic and catabolic reactions. B) ATP is formed in catabolic reactions. C) ADP is formed in anabolic reactions. D) Anabolic reactions are degradative.

Answer: D

3) The term used to describe a disease-causing microorganism is A) microbe. B) bacterium. C) virus. D) pathogen. E) infection.

Answer: D

3) Which of the following is NOT a characteristic inherent of the non-endospore-forming gram-positive rods? A) are aerotolerant B) carry out fermentative metabolism C) display a branched filamentous morphology D) nonpathogenic E) lack cell walls

Answer: D

3) Which of the following pairs is mismatched? A) nigrosin — negative stain B) methylene blue — simple stain C) acidic dye — capsule stain D) basic dye — negative stain E) crystal violet — simple stain

Answer: D

3) Which of the following statements about the oomycote algae is FALSE? A) They form hyphae. B) They produce zoospores in a sporangium. C) They cause plant diseases. D) They have chlorophyll. E) They reproduce sexually.

Answer: D

3) Which of the following statements is FALSE? A) DNA polymerase joins nucleotides in one direction only. B) The leading strand of DNA is made continuously. C) The lagging strand of DNA is started by an RNA primer. D) DNA replication proceeds in one direction around the bacterial chromosome. E) Multiple replication forks are possible on a bacterial chromosome.

Answer: D

31) Which of the following statements regarding the Entner-Doudoroff pathway is TRUE? A) It involves glycolysis. B) It involves the pentose phosphate pathway. C) NADH is generated. D) ATP is generated. E) NADH and ATP are generated.

Answer: D

32) An experiment began with 4 cells and ended with 128 cells. How many generations did the cells go through? A) 64 B) 32 C) 6 D) 5 E) 4

Answer: D

33) Which microscope uses two beams of light to produce a three-dimensional color image? A) fluorescence microscope B) phase-contrast microscope C) darkfield microscope D) DIC microscope E) electron microscope

Answer: D

33) 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

Answer: D

33) Which of the following statements about viruses is FALSE? A) Viruses contain DNA or RNA but never both. B) Viruses contain a protein coat. C) Viruses use the anabolic machinery of the cell. D) Viruses use their own catabolic enzymes. E) Viruses have genes.

Answer: D

34) All of the following are true regarding NK cells EXCEPT A) they are a type of lymphocyte. B) they are found in tissues of the lymphatic system. C) they have the ability to kill infected body cells and some tumor cells. D) they destroy infected body cells by phagocytosis. E) they release toxic substances that cause cell lysis or apoptosis.

Answer: D

34) Ethylene oxide A) is a good antiseptic. B) is not sporicidal. C) requires high heat to be effective. D) is a sterilizing agent. E) is the active chemical in household bleach.

Answer: D

34) Into which group would you place a multicellular heterotroph with chitin cell walls? A) Animalia B) Archaea C) Bacteria D) Fungi E) Plantae

Answer: D

35) Fungal infections are studied by A) virologists. B) bacteriologists. C) parasitologists. D) mycologists. E) herpetologists.

Answer: D

36) Gram-negative septic shock results from the following events. What is the second step? A) Body temperature is reset in the hypothalamus. B) Fever occurs. C) IL-1 is released. D) LPS is released from gram-negative bacteria. E) Phagocytes ingest gram-negative bacteria.

Answer: D

36) Macrophages arise from which of the following? A) basophils B) eosinophils C) lymphocytes D) monocytes E) neutrophils

Answer: D

36) Vaccinations are available for all of the following diseases EXCEPT A) measles. B) rubella. C) mumps. D) strep throat. E) hepatitis B.

Answer: D

36) Which of the following statements regarding the glycolysis pathway is FALSE? A) Two pyruvate molecules are generated. B) Four ATP molecules are generated via substrate-level phosphorylation. C) Two NADH molecules are generated. D) One molecule of ATP is expended. E) Two molecules of water are generated.

Answer: D

36) You have isolated an aerobic gram-positive, endospore-forming bacterium that grows well on nutrient agar. To which of the following groups does it most likely belong? A) phototrophic bacteria B) gammaproteobacteria C) deltaproteobacteria D) bacillales E) The answer cannot be determined based on the information provided.

Answer: D

37) 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

Answer: D

38) All of the following are iron-binding proteins found in humans EXCEPT A) lactoferrin. B) transferrin. C) hemoglobin. D) siderophorin. E) ferritin.

Answer: D

38) Which of the following statements about drugs that competitively inhibit DNA polymerase or RNA polymerase is FALSE? A) They cause mutations. B) They are used against viral infections. C) They can affect host cell DNA. D) They cause cellular plasmolysis. E) They interfere with protein synthesis.

Answer: D

38) Which one of the following does NOT belong with the others? A) Coxiella B) Ehrlichia C) Rickettsia D) Staphylococcus E) Wolbachia

Answer: D

39) An enzyme that catalyzes the cutting and resealing of DNA, and is translated from insertion sequences, is A) RNA polymerase. B) DNA ligase. C) DNA helicase. D) transposase. E) DNA polymerase.

Answer: D

39) In a hypertonic solution, a bacterial cell will typically A) lyse. B) burst. C) stay the same. D) plasmolyze. E) osmolyze.

Answer: D

39) Which of the following is NOT an example of microbial antagonism? A) acid production by bacteria B) bacteriocin production C) bacteria occupying host receptors D) bacteria causing disease E) bacteria producing vitamin K

Answer: D

39) You find colorless areas in cells in a gram-stained smear. What should you apply next? A) an acid-fast stain B) a flagella stain C) a capsule stain D) an endospore stain E) a simple stain

Answer: D

4) The major significance of Robert Koch's work is that A) microorganisms are present in a diseased animal. B) diseases can be transmitted from one animal to another. C) microorganisms can be cultured. D) microorganisms cause disease. E) microorganisms are the result of disease.

Answer: D

4) Which of the following is the best definition of epitope? A) specific regions on antigens that interact with T-cell receptors B) specific regions on antigens that interact with MHC class molecules C) specific regions on antigens that interact with haptens D) specific regions on antigens that interact with antibodies E) specific regions on antigens that interact with perforins

Answer: D

40) All of the following bacteria are motile. Which does NOT have flagella? A) Escherichia B) helical bacteria C) Pseudomonas D) spirochetes E) Salmonella

Answer: D

40) Repair of damaged DNA might be viewed as a race between an endonuclease and A) DNA ligase. B) DNA polymerase. C) helicase. D) methylase. E) primase.

Answer: D

40) Which of the following statements about natural killer cells is FALSE? A) They destroy virus-infected cells. B) They destroy tumor cells. C) They destroy cells lacking MHC I. D) They are stimulated by an antigen. E) None of the answers are correct; all of these statements are true.

Answer: D

41) All of the following are components of the inflammatory process EXCEPT A) dilation of blood vessels. B) release of histamines and prostaglandins. C) chemotaxis. D) diapedesis. E) antibody synthesis.

Answer: D

41) All of the following are methods of food preservation EXCEPT A) desiccation. B) high pressure. C) ionizing radiation. D) microwaves. E) osmotic pressure.

Answer: D

41) The cancer gene ras produces mRNA containing an extra exon that includes a number of UAA codons. Cancer cells produce ras mRNA missing this exon. This mistake most likely is due to a mistake by A) a chemical mutagen. B) DNA polymerase. C) photolyases. D) snRNPs. E) UV radiation.

Answer: D

41) Which enzyme catalyzes the reaction: O2- + O2- + 2H+ → H2O2 + O2? A) catalase B) oxidase C) peroxidase D) superoxide dismutase

Answer: D

41) Which of the following bacteria does NOT belong with the others? A) Halobacterium B) Halococcus C) Methanobacterium D) Staphylococcus E) Sulfolobus

Answer: D

41) Which one of the following steps does NOT occur during multiplication of a picornavirus? A) synthesis of + strands of RNA B) synthesis of - strands of RNA C) synthesis of viral proteins D) synthesis of DNA E) None of the answers is correct.

Answer: D

43) Normal microbiota are typically found in and on all the following body locations EXCEPT the A) skin. B) mouth. C) colon. D) blood. E) upper respiratory system.

Answer: D

43) The miRNAs in a cell A) are found in prokaryotic cells. B) are a part of the prokaryotic ribosome. C) are a part of the eukaryotic ribosome. D) allow different cells to produce different proteins. E) are responsible for inducing operons.

Answer: D

44) 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 of a fungus and a protozoan. E) they serve as primary producers in rocky ecosystems.

Answer: D

44) Untreated sewage is released into a river. Which of the following statements is FALSE? A) The untreated sewage is a health hazard. B) The untreated sewage increases the BOD. C) The untreated sewage decreases the dissolved oxygen. D) The untreated sewage kills bacteria. E) All of the statements are true.

Answer: D

44) Which of the following is NOT a functionally analogous pair? A) nucleus -nucleiod region B) mitochondria - prokaryotic plasma membrane C) chloroplasts - thylakoids D) cilia - pili E) 9+2 flagella - bacterial flagella

Answer: D

45) Bacteria that emit light can be used as biosensors because they A) migrate to hazardous chemical. B) do not emit light in the presence of a hazardous chemical. C) degrade hazardous chemicals. D) have FMN. E) have the lux gene.

Answer: D

45) Patients with indwelling catheters are susceptible to infections because A) injected solutions are contaminated. B) their immune systems are weakened. C) infections can be transmitted from other people. D) biofilms develop on catheters. E) bacteria cause infections.

Answer: D

45) Use of antibiotics in animal feed leads to antibiotic-resistant bacteria because A) bacteria from other animals replace those killed by the antibiotics. B) the few surviving bacteria that are affected by the antibiotics develop immunity to the antibiotics, which they pass on to their progeny. C) the antibiotics cause new mutations to occur in the surviving bacteria, which results in resistance to antibiotics. D) the antibiotics kill susceptible bacteria, but the few that are naturally resistant live and reproduce, and their progeny repopulate the host animal. E) the antibiotics persist in soil and water.

Answer: D

45) Which of the following statements about IL-12 is FALSE? A) It activates macrophages. B) It inhibits some tumor cells. C) It activates the TH1 pathway. D) It causes autoimmune diseases. E) It causes TH cells to respond to HIV.

Answer: D

5) Which of the following statements about members of the Kingdom Plantae is FALSE? A) They are multicellular. B) They are composed of eukaryotic cells. C) They undergo photosynthesis. D) They use organic carbon sources. E) They synthesize organic molecules.

Answer: D

6) Bacteriophages and animal viruses do NOT differ significantly in which one of the following steps? A) attachment B) penetration C) uncoating D) biosynthesis E) release

Answer: D

6) If cells are grown in media containing amino acids labeled with radioactive nitrogen (15N), most of radioactivity will be found in the cells' A) DNA. B) proteins. C) phospholipids. D) DNA and proteins. E) DNA and phospholipids.

Answer: D

6) The formal system for classifying and naming organisms was developed by A) Robert Koch. B) Ignaz Semmelweis. C) Aristotle. D) Carolus Linnaeus. E) Louis Pasteur.

Answer: D

6) Which of the following is NOT a typical characteristic of most bacterial plasma membranes? A) site of energy production B) composed of a phospholipid bilayer C) contains proteins D) contains cholesterol E) is selectively permeable

Answer: D

7) The purpose of a mordant in the Gram stain is to A) remove the simple stain. B) make the bacterial cells larger. C) make the flagella visible. D) prevent the crystal violet from leaving the cells. E) make gram-negative cells visible.

Answer: D

7) Which of the following cells is NOT an APC? A) dentritic cells B) macrophages C) immature B cells D) natural killer cells E) None of the answers is correct; all of these are APCs.

Answer: D

8) A bacterial species differs from a species of eukaryotic organisms in that a bacterial species A) does not breed with other species. B) has a limited geographical distribution. C) can be distinguished from other bacterial species. D) is a population of cells with similar characteristics. E) breeds with its own species.

Answer: D

8) All of the following are used in secondary sewage treatment EXCEPT A) trickling filters. B) bulking and floc formation. C) aeration. D) anaerobic digestion. E) activated sludge.

Answer: D

9) The negative stain is used to A) visualize endospores. B) determine Gram reaction. C) determine flagella arrangement. D) visualize capsules. E) determine cell size.

Answer: D

9) Which of the following is NOT a characteristic of spirochetes? A) possess an axial filament B) gram-negative C) helical shape D) easily observed with brightfield microscopy E) found in the human oral cavity

Answer: D

9) Which of the following is a limitation of the autoclave? A) It requires an excessively long time to achieve sterilization. B) It cannot inactivate viruses. C) It cannot kill endospores. D) It cannot be used with heat-labile materials. E) It cannot be used with glassware.

Answer: D

9) Which of the following pairs is mismatched? A) endoplasmic reticulum & internal transport B) Golgi complex & secretion C) mitochondria & ATP production D) centrosome & food storage E) lysosome & digestive enzymes

Answer: D

1) Microorganisms are involved in each of the following processes EXCEPT A) infection. B) decomposition of organic material. C) O2 production. D) food production. E) smog production.

Answer: E

1) Which of the following statements is INCORRECT regarding prokaryotic cells? A) Their DNA is not enclosed within a membrane. B) They lack membrane-enclosed organelles. C) They typically have a circular chromosome. D) They reproduce by binary fission. E) They lack a plasma membrane.

Answer: E

11) All of the following organisms are involved in carbon fixation EXCEPT A) green and purple sulfur bacteria. B) cyanobacteria. C) lichens. D) algae. E) mycorrhizae.

Answer: E

11) Protozoan motility structures include A) cilia. B) flagella. C) pseudopods. D) cilia and pseudopods only. E) cilia, flagella, and pseudopods.

Answer: E

11) The specificity of an antibody is due to A) its valence. B) the H chains. C) the L chains. D) the constant portions of the H and L chains. E) the variable portions of the H and L chains.

Answer: E

11) Which of the following is NOT based on nucleic-acid hybridization? A) DNA chip B) FISH C) PCR D) Southern blotting E) Western blotting

Answer: E

11) Which of the following pairs is mismatched? A) teleomorph — produces both sexual and asexual spores B) dermatomycosis — fungal infection of the skin C) dimorphic fungus — grows as a yeast or a mold D) systemic mycosis — fungal infection of body organs E) coenocytic hyphae — hyphae with cross-walls

Answer: E

12) Which of the following is NOT a characteristic of B cells? A) They originate in bone marrow. B) They have antibodies on their surfaces. C) They are responsible for the memory response. D) They are responsible for antibody formation. E) They recognize antigens associated with MHC I.

Answer: E

13) Genetic change in bacteria can be brought about by A) mutation. B) conjugation. C) transduction. D) transformation. E) All of the answers are correct.

Answer: E

13) Which microscope achieves the highest magnification and greatest resolution? A) compound light microscope B) phase-contrast microscope C) darkfield microscope D) fluorescence microscope E) electron microscope

Answer: E

13) Which of the following antibiotics is recommended for use against gram-negative bacteria? A) polyenes B) bacitracin C) cephalosporin D) penicillin E) polymyxin

Answer: E

14) Disinfection of water is achieved by all of the following EXCEPT A) ozone. B) UV radiation. C) chlorine. D) copper sulfate. E) peracetic acid.

Answer: E

14) In using this microscope, the observer does NOT look directly at an image through a lens. A) compound light microscope B) phase-contrast microscope C) darkfield microscope D) fluorescence microscope E) electron microscope

Answer: E

14) Which of the following provides taxonomic information that includes the others? A) nucleic acid hybridization B) nucleic acid-base composition C) amino acid sequencing D) biochemical tests E) cladogram

Answer: E

14) Which of the following statements about nosocomial infections is FALSE? A) They occur in compromised patients. B) They may be caused by opportunists. C) They may be caused by drug-resistant bacteria. D) They may be caused by normal microbiota. E) The patient was infected before hospitalization.

Answer: E

15) Which of the following statements is FALSE? A) A prophage is phage DNA inserted into a bacterial chromosome. B) A prophage can "pop" out of the chromosome. C) Prophage genes are repressed by a repressor protein coded for by the prophage. D) A prophage may result in new properties of the host cell. E) The prophage makes the host cell immune to infection by other phages.

Answer: E

16) Which of the following is NOT a reservoir of infection? A) a sick person B) a healthy person C) a sick animal D) a hospital E) None of the answers is correct; all of these can be reservoirs of infection.

Answer: E

17) The antibodies that can bind to large parasites are A) IgG. B) IgM. C) IgA. D) IgD. E) IgE.

Answer: E

17) The antimicrobial effects of AMPs include all of the following EXCEPT A) inhibition of cell wall synthesis. B) lysis of bacterial cells. C) destruction of nucleic acids. D) pore formation in bacterial membranes. E) inhibition of phagocytosis.

Answer: E

17) Which of the following pairs is mismatched? A) dinoflagellates & paralytic shellfish poisoning B) brown algae & algin C) red algae & agar D) diatoms & petroleum E) green algae & prokaryotic

Answer: E

18) A microorganism measures 5 μm in length. Its length in mm would be A) 500 mm. B) 50 mm. C) 0.5 mm. D) 0.05 mm. E) 0.005 mm.

Answer: E

18) All of the following factors contribute to hospital-acquired infections EXCEPT A) some bacteria metabolize disinfectants. B) gram-negative bacteria are often resistant to disinfectants. C) invasive procedures can provide a portal of entry for bacteria. D) bacteria may be present in commercial products such as mouthwash. E) None of the answers is correct; all of these factors may contribute to hospital-acquired infection.

Answer: E

18) Functions of the glycocalyx include all of the following EXCEPT A) biofilm formation. B) increased virulence. C) source of nutrition. D) protection against dehydration. E) binary fission.

Answer: E

18) Which of the following is a fomite? A) water B) droplets from a sneeze C) pus D) insects E) a hypodermic needle

Answer: E

19) An envelope is acquired during which of the following steps? A) penetration B) adsorption C) uncoating D) biosynthesis E) release

Answer: E

19) Which of the following cytopathic effects is cytocidal? A) inclusion bodies B) giant cells C) antigenic changes D) transformation E) release of enzymes from lysosomes

Answer: E

2) What type of immunity results from transfer of antibodies from one individual to a susceptible individual by means of injection? A) innate immunity B) naturally acquired active immunity C) naturally acquired passive immunity D) artificially acquired active immunity E) artificially acquired passive immunity

Answer: E

2) Which of the following statements is TRUE? A) At least one member must not benefit in a symbiotic relationship. B) Members of a symbiotic relationship cannot live without each other. C) A parasite is not in symbiosis with its host. D) Symbiosis refers to different organisms living together and benefiting from each other. E) At least one member must benefit in a symbiotic relationship.

Answer: E

20) All of the following are used by bacteria to attach to host cells EXCEPT A) M protein. B) ligands. C) fimbriae. D) capsules. E) A-B toxins.

Answer: E

20) In the malaria parasite life cycle A) humans are the intermediate host. B) mosquitoes are the definitive host. C) mosquitoes are the vector. D) humans are the intermediate host and mosquitos are the definitive host. E) humans are the intermediate host and mosquitoes are both the definitive host and the vector.

Answer: E

20) Which of the following definitions is INCORRECT? A) acute: a short-lasting primary infection B) inapparent: infection characteristic of a carrier state C) chronic: a disease that develops slowly and lasts for months D) primary infection: an initial illness E) secondary infection: a long-lasting illness

Answer: E

20) Which of the following statments is NOT true of lysogeny? A) It can give infected pathogens the genetic information for toxin production. B) Prophage is inserted into the host genome. C) Lytic cycle may follow lysogeny. D) It is a "silent" infection; the virus does not replicate. E) It causes lysis of host cells.

Answer: E

21) 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.

Answer: E

21) Which of the following regarding antimicrobial control agents is FALSE? A) Contaminating organic debris such as blood or sputum will decrease effectiveness. B) Some agents kill by denaturing microbial cell proteins. C) Some agents affect microbial cell membranes by dissolving lipids. D) Some agents are utilized as both an antiseptic and a disinfectant. E) A true antimicrobial control agent is equally effective against both bacteria and viruses.

Answer: E

21) Which of the following statements about the causative agent of Rocky Mountain spotted fever is FALSE? A) It is an intracellular parasite. B) It is transmitted by ticks. C) It is in the genus Rickettsia. D) It is gram-negative. E) It is found in soil and water.

Answer: E

22) All of the following are effects of histamine EXCEPT A) destruction of an injurious agent. B) removal of an injurious agent. C) isolation of an injurious agent. D) repair of damaged tissue. E) production of antibodies.

Answer: E

22) Regarding Louis Pasteur's experiments with the S-neck flask, which of the following statements is TRUE? A) Air exchange was involved. B) A food source was provided. C) The possibility of contamination was removed. D) All preexisting microorganisms were killed. E) All of the answers are correct.

Answer: E

23) The antimicrobial drugs with the broadest spectrum of activity are A) aminoglycosides. B) chloramphenicol. C) penicillin G. D) macrolides. E) tetracyclines.

Answer: E

23) 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

Answer: E

23) Which one of the following bacteria does NOT belong with the others? A) Bordetella B) Burkholderia C) Campylobacter D) Pseudomonas E) Salmonella

Answer: E

24) Emergence of infectious diseases can be attributed to all of the following EXCEPT A) antibiotic resistance. B) climatic changes. C) new strains of previously known agents. D) ease of travel. E) None of the answers is correct; the emergence of infectious diseases can be attributed to all of these.

Answer: E

25) Which of the following pairs is mismatched? A) malaria vector B) salmonellosis vehicle transmission C) syphilis direct contact D) influenza droplet infection E) None of the pairs is mismatched.

Answer: E

25) Which of the following results in lethal damage to nucleic acids? A) heat B) radiation C) certain chemicals D) heat and radiation E) heat, radiation, and some chemicals

Answer: E

26) Mycology is the study of A) mycoplasma. B) mushrooms. C) protozoa. D) molds. E) molds, yeast, and mushrooms.

Answer: E

26) Which of the following can contribute to postoperative infections? A) using syringes more than once B) normal microbiota on the operating room staff C) errors in aseptic technique D) antibiotic resistance E) All of the answers are correct.

Answer: E

27) One of the most popular taxonomic tools is DNA fingerprinting to develop profiles of organisms. These profiles provide direct information about A) enzymatic activities. B) protein composition. C) the presence of specific genes. D) antigenic composition. E) the similarities between nucleotide sequences.

Answer: E

27) Residual chlorine must be maintained in A) anaerobic sludge digestion. B) primary sewage treatment. C) secondary sewage treatment. D) tertiary sewage treatment. E) water treatment.

Answer: E

28) A cold transmitted by a facial tissue is an example of A) direct contact. B) droplet transmission. C) fomite. D) vector. E) vehicle transmission.

Answer: E

3) The function of the "ciliary escalator" is to A) propel inhaled dust and microorganisms toward the throat. B) remove microorganisms from the gastrointestinal tract. C) remove microorganisms from the lower respiratory tract. D) remove microorganisms from the upper respiratory tract. E) trap inhaled dust and microorganisms in mucous and propel it away from the lower respiratory tract.

Answer: E

3) Which of the following is NOT a symbiotic pair of organisms? A) elk and rumen bacteria B) orchid and mycorrhizae C) onions and arbuscules D) bean plant and Rhizobium E) sulfur and Thiobacillus

Answer: E

3) Which of the following statements about viral spikes is FALSE? A) They are composed of carbohydrate-protein complexes. B) They are used for attachment. C) They may cause hemagglutination. D) They bind to receptors on the host cell surface. E) They are found only on nonenveloped viruses.

Answer: E

31) What is the total magnification of a specimen viewed with a 10x ocular lens and a 45x objective lens? A) 4.5x B) 10x C) 45x D) 100x E) 450x

Answer: E

32) Antibiotics are produced by A) viruses. B) bacteria. C) protozoa. D) fungi. E) bacteria and fungi.

Answer: E

32) In the microscope, you observe multinucleated amoeboid cells with sporangia that form spores. This is a(n) A) ascomycete. B) cellular slime mold. C) Euglenozoa. D) tapeworm. E) plasmodial slime mold.

Answer: E

33) An iodophor is a(n) A) phenol. B) agent that reduces oxygen. C) quaternary ammonium compound. D) form of formaldehyde. E) iodine mixed with a surfactant.

Answer: E

C) Serological test for antibodies

40) A 25-year-old man presented with fever, malaise, and a rash on his chest, arms, and feet. Which of the following will be most useful for a rapid diagnosis? A) Bacterial culture B) Microscopic examination of blood C) Serological test for antibodies D) Serological test for antigen E) Viral culture

C) Secondary

41) A 25-year-old man presented with fever, malaise, and a rash on his chest, arms, and feet. Diagnosis was based on serological testing. The patient then reported that he had an ulcer on his penis 2 months earlier. What stage of disease is the patient in? A) NGU B) Primary C) Secondary D) Tertiary

D) Penicillin.

42) A 25-year-old male presented with fever, malaise, and a rash on his chest, arms, and feet. Diagnosis was based on serological testing. The patient then reported that he had an ulcer on his penis 2 months earlier. This disease can be treated with A) Acyclovir. B) Metronidazole. C) Miconazole. D) Penicillin. E) Surgery.

A) Acyclovir

43) A pelvic examination of a 23-year-old woman showed vesicles and ulcerated lesions on her labia. Cultures were negative for Neisseria and Chlamydia; the VDRL test was negative. Which treatment is appropriate? A) Acyclovir B) Metronidazole C) Miconazole D) Penicillin E) Surgery

B) Genital herpes

44) A pelvic examination of a 23-year-old woman showed vesicles and ulcerated lesions on her labia. Cultures were negative for Neisseria and Chlamydia; the VDRL test was negative. Which of the following is probable? A) Candidiasis B) Genital herpes C) Gonorrhea D) NGU E) Syphilis

C) Neisseria gonorrhoeae

45) Which of the following is treated with cephalosporins because the organism is resistant to penicillin and fluoroquinolones? A) Mycoplasma hominis B) Haemophilus ducreyi C) Neisseria gonorrhoeae D) Treponema pallidum E) Gardnerella vaginalis

C) Escherichia coli.

5) Pyelonephritis usually is caused by A) Pseudomonas aeruginosa. B) Proteus spp. C) Escherichia coli. D) Enterobacter aerogenes. E) Streptococcus pyogenes.

C) Domestic dogs.

6) The reservoir for leptospirosis is A) Humans. B) Water. C) Domestic dogs. D) Domestic cats. E) Hospitals.

E) Trichomoniasis

7) Which of the following is NOT primarily a sexually transmitted infection (STI)? A) Lymphogranuloma venereum B) Genital herpes C) Gonorrhea D) Chancroid E) Trichomoniasis

D) Syphilis

8) Which of the following is treated with penicillin? A) Lymphogranuloma venereum B) Genital warts C) Candidiasis D) Syphilis E) Trichomoniasis

A) Trichomoniasis - fungus

9) Which of the following pairs is mismatched? A) Trichomoniasis - fungus B) Gonorrhea - gram-negative cocci C) Chancroid - gram-negative rod D) Gardnerella - clue cells E) Syphilis - gram

33) Which of the following is NOT a predisposing factor of disease? A) lifestyle B) genetic background C) climate D) occupation E) None of the answers are correct; all of these are predisposing factors of disease.

Answer: E

34) Filtration to remove protozoa occurs in A) anaerobic sludge digestion. B) primary sewage treatment. C) secondary sewage treatment. D) tertiary sewage treatment. E) water treatment.

Answer: E

34) Which of the following pairs is mismatched? A) nematodes — complete digestive tract B) cestodes — segmented body made of proglottids C) trematodes — flukes D) nematodes — many are free-living E) cestodes — all are free-living

Answer: E

35) In which of the following patterns of disease does the patient experience no signs or symptoms? A) prodromal B) decline C) convalescence D) incubation E) incubation and convalescence

Answer: E

35) The following events occur in cellular immunity. What is the third step? A) Antibodies are produced. B) Dendritic cell takes up antigen. C) Antigen enters M cell. D) TH cell produces cytokines. E) TH cells proliferate.

Answer: E

35) The mechanism by which the presence of arabinose controls the arabinose operon is A) catabolite repression. B) translation. C) DNA polymerase. D) repression. E) induction.

Answer: E

35) Where are phospholipids most likely found in a eukaryotic cell? A) surrounding flagella B) around organelles C) the plasma membrane D) ribosomes E) the plasma membrane, around organelles, and surrounding flagella

Answer: E

36) Which microscope is used to see detail of a 300-nm virus? A) fluorescence microscope B) phase-contrast microscope C) darkfield microscope D) DIC microscope E) electron microscope

Answer: E

37) Recombinant DNA refers to the A) study of bacterial ribosomes. B) study of the function of genes. C) interaction between human and bacterial cells. D) synthesis of proteins from genes. E) DNA resulting when bacterial genes are inserted in an animal genome.

Answer: E

37) Which of the following pairs is mismatched? A) spirochete & axial filament B) aerobic, helical bacteria & gram-negative C) enterics & gram-negative D) mycobacteria & acid-fast E) Pseudomonas & gram-positive

Answer: E

37) Which of the following statements is correct about diffusion? A) It requires an expenditure of energy by the cell. B) It is a passive process in which molecules move from a region of higher concentration to a region of lower concentration. C) It is an active process in which molecules move from a region of lower concentration to one of higher concentration. D) It may require a transport protein. E) It involves movement of molecules down a concentration gradient and may require a transport protein.

Answer: E

37) Which one of the following causes transmembrane channels in target cells? A) granzymes B) hapten C) IL-1 D) IL-2 E) perforin

Answer: E

38) Molecular biology is the study of A) DNA synthesis. B) RNA replication. C) protein synthesis. D) enzyme function. E) the structure and function of macromolecules essential to life.

Answer: E

38) The following steps occur during multiplication of herpesviruses. Which is the third step? A) attachment B) biosynthesis C) penetration D) release E) uncoating

Answer: E

38) The method of transmission of the disease in Situation 14.1 was A) direct contact. B) droplet. C) indirect contact. D) vector-borne. E) vehicle.

Answer: E

38) Which of the following is NOT a cytopathic effect of viruses? A) cell death B) host cells fusing to form multinucleated syncytia C) inclusion bodies forming in the cytoplasm or nucleus D) increased cell growth E) toxin production

Answer: E

38) Which of the following is NOT characteristic of fecal coliforms? A) gram-negative B) non-spore forming C) rod-shaped D) lactose-fermenting E) pathogenic

Answer: E

39) All of the following occur during inflammation. What is the first step? A) diapedesis B) margination C) phagocyte migration D) repair E) vasodilation

Answer: E

39) Microorganisms are essential to our life. Each of the following is an example of a beneficial function of microorganisms EXCEPT A) alternative fuel production. B) bioremediation. C) gene therapy. D) agriculture. E) increased morbidity.

Answer: E

4) Common commercial benefits of microorganisms include synthesis of A) antibiotics. B) aspirin. C) insulin. D) antibiotics and aspirin. E) antibiotics and insulin.

Answer: E

40) The major food producers for other living organisms is/are A) higher plants. B) cyanobacteria. C) algae. D) higher plants and algae. E) higher plants, cyanobacteria, and algae.

Answer: E

40) Which microscope is best used for observing the surfaces of intact cells and viruses? A) phase-contrast microscope B) darkfield microscope C) fluorescence microscope D) brightfield microscope E) scanning electron microscope

Answer: E

40) Which of the following pairs is mismatched? A) ionizing radiation — hydroxyl radicals B) ozone — takes electrons from substances C) plasma sterilization — free radicals D) supercritical fluids — CO2 E) ultraviolet radiation — desiccation

Answer: E

41) Gene therapy is currently used to treat all of the following diseases EXCEPT A) severe combined immunodeficiency disease (SCID). B) Duchenne's muscular dystrophy. C) cystic fibrosis. D) LDL-receptor deficiency. E) colon cancer.

Answer: E

41) Which of the following does NOT affect eukaryotic cells? A) antiprotozoan drugs B) antihelminthic drugs C) antifungal drugs D) nucleotide analogs E) semisynthetic penicillins

Answer: E

42) Into which group would you place a photosynthetic organism that lacks a nucleus and has a thin peptidoglycan wall surrounded by an outer membrane? A) Animalia B) Fungi C) Plantae D) Firmicutes (gram-positive bacteria) E) Proteobacteria (gram-negative bacteria)

Answer: E

42) Which one of the following is NOT a zoonosis? A) cat-scratch disease B) Hantavirus pulmonary syndrome C) rabies D) tapeworm E) None of the answers is correct; all of these are zoonoses.

Answer: E

43) If you were preparing nutrient agar at home and did not have an autoclave, what could you use to sterilize the nutrient agar? A) bleach B) boiling for one hour C) hydrogen peroxide D) oven at 121°C for one hour E) pressure cooker at 121°C for 15 minutes

Answer: E

44) Bone and tendons for transplant are decontaminated by A) ethylene oxide. B) glutaraldehyde. C) peroxygens. D) plasma sterilization. E) supercritical fluids.

Answer: E

44) Burkholderia was reclassified from the gammaproteobacteria to the betaproteobacteria because A) it grows in disinfectants. B) it is a gram-negative rod. C) it causes infections in cystic fibrosis patients. D) it causes melioidosis. E) its rRNA sequence is similar to that of Neisseria.

Answer: E

45) Data collected to date indicate that A) humans and marine mammals cannot be infected by the same pathogens. B) marine mammals do not get infectious diseases. C) new species of bacteria may be discovered in wild animals. D) marine mammals don't have an immune system. E) None of the answers is correct.

Answer: E

45) Protein synthesis in eukaryotes is similar to the process in prokaryotes in that both eukaryotes and prokaryotes A) have exons. B) have introns. C) require snRNPS. D) use methionine as the "start" amino acid. E) use codons to determine polypeptide sequences.

Answer: E

45) The crab industry needs female crabs for growing more crabs. What bacterium might be used to ensure development of female crabs and shrimp? A) Acinetobacter B) Gemmata C) Neisseria D) Pelagibacter E) Wolbachia

Answer: E

5) In what way are semisynthetic penicillins and natural penicillins alike? A) Both are broad spectrum. B) Both are resistant to penicillinase. C) Both are resistant to stomach acids. D) Both are bactericidal. E) Both are based on β-lactam.

Answer: E

5) Which of the following is NOT a verified exception in the use of Koch's postulates? A) Some diseases have poorly defined etiologies. B) Some pathogens can cause several disease conditions. C) Some human diseases have no other known animal host. D) Some diseases are not caused by microbes. E) Some diseases are noncommunicable.

Answer: E

6) What is the fate of pyruvic acid in an organism that uses aerobic respiration? A) It is reduced to lactic acid. B) It reacts with oxaloacetate to form citrate. C) It is oxidized in the electron transport chain. D) It is catabolized in glycolysis. E) It is converted into acetyl CoA.

Answer: E

6) Which of the following pairs is mismatched? A) Basidiomycota — basidiospores B) Ascomycota — conidiospores C) Zygomycota — sporangiospores D) microsporidia — lack mitochondria E) anamorphs — lack spores

Answer: E

6) 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.

Answer: E

7) Which of the following elements is NOT correctly matched with its cellular function? A) nitrogen — needed for amino acid synthesis B) phosphorus — incorporated into nucleic acids C) sulfur — used for synthesis of thiamin and biotin D) magnesium and potassium — required as cofactors for enzymes E) None of the answers is correct; all of the elements are correctly matched.

Answer: E

A pigment produced by an opportunistic pathogen that contributes to tissue damage is a) pyocyanin b) streptokinase c) hyaluronidase d) lipase e) M protein

A

Anthrax derives its name from which of the following aspects of the disease? a) the appearance of eschars on the skin b) the necessity of burning animals killed by the disease c) the shape of B. anthracis colonies on agar d) the microscopic appearance of its cells e) the shape of its endospores

A

Sporotrichosis is more commonly known as a) rose-gardener's disease b) ringworm c) white piedra d) herpangina e) scabies

A

The skin is an effective barrier against invading microbes because a) the outer layers are dead and covered in salt. b) no microbes are able to survive on the surface. c) it is well supplied with blood vessels to flush microbes from the surface. d) the surface is covered in salt. e) the outer layers of cells are dead

A

32) You are studying a cell structure that is approximately 100 nm in size. Which of the following provides the lowest magnification you can use to see this structure? ) brightfield microscope B) darkfield microscope C) transmission electron microscope D) phase-contrast microscope E) scanning electron microscope

A Answer: E

7) Which of the following regarding antimicrobial control agents is FALSE? A) Contaminating organic debris such as blood or sputum decrease effectiveness. B) Some agents kill by denaturing microbial cell proteins. C) Some agents affect microbial cell membranes by dissolving lipids. D) Silver is used for treating antibiotic-resistant bacteria. E) Some agents inactivate viruses by attacking cell membrane lipids.

Answer: E

7) Which one of the following does NOT belong with the others? A) bacitracin B) cephalosporin C) monobactam D) penicillin E) streptomycin

Answer: E

8) When an antibody binds to a toxin, the resulting action is referred to as A) agglutination. B) opsonization. C) ADCC. D) apoptosis. E) neutralization.

Answer: E

8) Which of the following is NOT an enteric? A) Salmonella B) Shigella C) Escherichia D) Enterobacter E) Campylobacter

Answer: E

1) Any process that destroys the non-spore forming contaminants on inanimate objects is sterilization.

Answer: FALSE

1) In general, the LD50 for exotoxins is much greater than the LD50 for endotoxins.

Answer: FALSE

1) In water treatment, the purpose of flocculation is to remove microbes, such as Giardia and Cryptosporidium.

Answer: FALSE

1) Infectious disease is almost totally eradicated in our world.

Answer: FALSE

1) The dermis is composed of connective tissue and provides protection from the external environment.

Answer: FALSE

10) All pathogens known to infect humans have been identified at this point in time.

Answer: FALSE

10) Cell-to-cell contact is required for transduction to occur.

Answer: FALSE

10) Microorganisms placed in high concentrations of salts and sugars undergo lysis.

Answer: FALSE

10) Most cases of hookworm infection are acquired by ingestion of eggs in contaminated food or water.

Answer: FALSE

10) Phage therapy has been used in the past as an antiviral treatment.

Answer: FALSE

10) The human body is typically free of archaeal species.

Answer: FALSE

10) When haptens attach to carrier molecules, an epitope forms on hapten which then can be bound to antibody.

Answer: FALSE

2) A viroid is a completely developed infectious agent composed of nucleic acid and surrounded by a capsid.

Answer: FALSE

2) Desiccation is a reliable form of sterilization.

Answer: FALSE

2) In a completed Gram stain, gram-negative bacteria are colorless.

Answer: FALSE

2) PABA serves as the competitive inhibitor in the action of sulfanilamides.

Answer: FALSE

2) The pentose phosphate pathway can be characterized as an anabolic pathway.

Answer: FALSE

3) Bacteria typically contain multiple chromosomes.

Answer: FALSE

3) Binomial nomenclature is used to name viruses.

Answer: FALSE

3) Cells placed in a hypotonic solution tend to lose water due to osmotic pressure.

Answer: FALSE

3) MMWR is a publication by the CDC that reports on only emerging diseases.

Answer: FALSE

3) Myxobacteria are classified as actinobacteria due to fungal-like lifestyle.

Answer: FALSE

3) Only dendritic cells produce interleukins.

Answer: FALSE

3) Pure cultures can easily be obtained on streak plates, even if the desired bacteria are present in very low concentrations.

Answer: FALSE

3) The process of pasteurization to reduce food spoilage utilizes high heat to kill all bacteria present.

Answer: FALSE

3) Undergrowth of fungi after antibiotic use is commonly referred to as a superinfection.

Answer: FALSE

4) A researcher only needs to select a cohort group when implementing an analytical epidemiological study.

Answer: FALSE

4) Glycoprotein spikes are found on the capsids of all viruses.

Answer: FALSE

4) If acid-fast bacteria are stained with the Gram stain, they will stain gram-negative.

Answer: FALSE

4) In A-B exotoxins, the A component binds to the host cell receptor so that the B component can enter the cell.

Answer: FALSE

4) The Gram stain is not suitable for identifying members of the Archaea.

Answer: FALSE

4) The Platyhelminthes group includes roundworms, tapeworms, and flukes.

Answer: FALSE

4) The highest level in the taxonomic hierarchy is "Kingdom."

Answer: FALSE

4) The inflammatory response can only be triggered by an infection.

Answer: FALSE

4) The production of interferons at an infection site is critical for chemotaxis.

Answer: FALSE

5) Diseases that are referred to as EIDs have only been discovered in the past fifty years.

Answer: FALSE

5) Spontaneous generation refers to living cells arising only from other living cells.

Answer: FALSE

5) The BOD is a measurement of the amount of bacteria present before and after the sewage treatment process.

Answer: FALSE

5) The miRNAs in a cell inhibit protein synthesis by forming complementary bonds with rRNA.

Answer: FALSE

5) The use of enzymes is necessary to increase the activation energy requirements of a chemical reaction.

Answer: FALSE

6) All gram-negative bacteria are classified as proteobacteria.

Answer: FALSE

6) At this point in time, scientists believe the vast majority of the domain Bacteria have been discovered.

Answer: FALSE

6) Compromised hosts are always suffering from suppressed immune systems.

Answer: FALSE

6) Endospores are a reproductive structure.

Answer: FALSE

6) Most pathogenic bacteria are thermophiles.

Answer: FALSE

6) Penicillin and streptomycin are commonly used in syngerism because they display the same mode of action.

Answer: FALSE

6) Some organisms may contain multiple genomes.

Answer: FALSE

6) The bacteriological safety of drinking water is determined by testing water samples for the presence of human pathogens.

Answer: FALSE

6) The variable region of the antibody is solely responsible the significant diversity of antigen targets.

Answer: FALSE

7) All cells possess a cell wall.

Answer: FALSE

7) Complement proteins act as opsonins by binding to microorganisms and promoting phagocytosis.

Answer: FALSE

7) Helical and icosahedral are terms used to describe the shapes of a virus envelope.

Answer: FALSE

7) In helminth life cycles, the organism that harbors the sexually reproductive phase of the parasite is called the intermediate host.

Answer: FALSE

7) In performing a ten-fold dilutions series from a sample containing 10,000 bacteria per milliliter, the fourth tube in the dilution series will have 10 cells per milliliter.

Answer: FALSE

7) Once a culture is purified, the next step in the process of identifying bacteria is biochemical testing.

Answer: FALSE

7) Only microbes produce antimicrobial peptides.

Answer: FALSE

7) Plasma cells will eventually differentiate into memory cells.

Answer: FALSE

7) The dense growth of algae in an algal bloom leads to increased oxygen levels in lakes that enhance the habitat for fish.

Answer: FALSE

7) The pH of the medium has no effect on the activity of the disinfectant being applied.

Answer: FALSE

8) Digestion of microorganisms occurs in phagosomes.

Answer: FALSE

8) Many enzymes in both prokaryotic and eukaryotic cells are compartmentalized within organelles.

Answer: FALSE

8) Memory cells do not require B cell receptors.

Answer: FALSE

8) Most symptoms of endotoxins can be treated with administration of anti-endotoxin antibodies.

Answer: FALSE

8) Photosynthetic organisms always produce oxygen gas as a metabolic byproduct.

Answer: FALSE

8) Reservoirs of infections are always animate objects.

Answer: FALSE

8) Some viruses can contain both DNA and RNA.

Answer: FALSE

8) The capsules and flagella of bacteria can be observed in gram-stained smears.

Answer: FALSE

8) Ultraviolet light (UV) causes irreversible breaks in DNA strands.

Answer: FALSE

8) Viruses are the only known infectious agents that are obligatory intracellular parasites.

Answer: FALSE

9) Both respiration and photosynthesis use water molecules for the donation of hydrogen ions.

Answer: FALSE

9) Bovine spongiform encephalitis (BSE, or "mad cow disease") is caused by a virus.

Answer: FALSE

9) Nitrogen fixation by bacteria occurs only in the root nodules of leguminous plants.

Answer: FALSE

9) The greater resolution of the electron microscope compared to the compound microscope is due to the longer wavelengths of the electrons used to examine specimens.

Answer: FALSE

9) The insect vectors have six legs and include ticks, mosquitoes, and lice.

Answer: FALSE

9) The number of organelles such as chloroplasts, mitochondria, and rough endoplasmic reticulum is the same in all eukaryotic cells.

Answer: FALSE

9) Transposition results in the formation of base substitution mutations in a cell's DNA.

Answer: FALSE

9) Western blotting is an immunological test used to identify the antigens in an individual suspected of having Lyme disease.

Answer: FALSE

True/False Questions 1) Apoptosis results in significant leakage of cellular contents.

Answer: FALSE

True/False Questions 1) Bacterial predators such as Bdellovibrio are members of the betaproteobacteria.

Answer: FALSE

True/False Questions 1) The cell membranes of all three domains are composed of straight carbon chains attached to glycerol by ester linkage.

Answer: FALSE

1) An antibiotic that attacks the LPS layer would be expected to have a narrow spectrum of activity.

Answer: TRUE

1) An isolated colony on a streak plate contains millions or billions of identical cells.

Answer: TRUE

1) Catabolic reactions are generally degradative and hydrolytic.

Answer: TRUE

1) For a particular disease at a specific time period, morbidity rates should always be equal or greater than mortality rates.

Answer: TRUE

1) Plasmogamy, karyogamy, and meiosis are stages of the fungal sexual life cycle.

Answer: TRUE

1) Recombination will always alter a cell's genotype.

Answer: TRUE

1) The basic mechanism of viral multiplication is similar for all viruses.

Answer: TRUE

1) The cell walls of bacteria are responsible for the shape of the bacteria and the difference in the Gram stain reaction.

Answer: TRUE

1) The counterstain used in the Gram stain is a basic dye.

Answer: TRUE

10) Both normal and transient flora can become opportunistic pathogens.

Answer: TRUE

10) If you observe rod-shaped red cells after the Gram stain, you can assume their cell walls contain endotoxin.

Answer: TRUE

10) In small communities lacking municipal sewage systems, sewage is treated in septic systems or oxidation ponds.

Answer: TRUE

10) Ingestion of certain lactic acid bacteria (LABs) has been shown to be beneficial for function and health of the intestinal tract.

Answer: TRUE

10) Many pathogens use the same portal for entry and exit from the body.

Answer: TRUE

10) Most drugs that interfere with viral multiplication also interfere with host cell function.

Answer: TRUE

10) Nitrogen-fixing bacteria, such as cyanobacteria, can use atmospheric nitrogen (N2) for their nitrogen source.

Answer: TRUE

10) Once an enzyme has converted substrates into products, the active site reverts back to its original form.

Answer: TRUE

10) Scanned probe microscopy is used to examine fine detail of molecular complexes, such as blood clots, or molecules, such as DNA.

Answer: TRUE

10) When building a cladogram, the length of the horizontal branch is based on the calculated percent similarity between organisms.

Answer: TRUE

2) A student has obtained a sample of pond water for study. Using the high-power lens, he observes several cells with nuclei. He can conclude that the cells are NOT bacteria.

Answer: TRUE

2) Antibiotics that target the cell wall are an effective treatment against many pathogenic bacteria.

Answer: TRUE

2) Arthropod vectors are blood-sucking animals such as ticks, lice, and fleas that transmit microbial pathogens.

Answer: TRUE

2) Bacterial growth refers to an increase in the numbers of cells in a bacterial culture.

Answer: TRUE

2) Biofilms provide pathogens with an adhesion mechanism and aid in resistance to antimicrobial agents.

Answer: TRUE

2) Bioremediation involves the use of microbes to degrade or detoxify pollutants.

Answer: TRUE

2) Chloroplasts possess circular DNA and reproduce by binary fission.

Answer: TRUE

2) Cytokines are protein-based chemical messengers that allow for communication between cells of the immune system.

Answer: TRUE

2) Microorganisms that are members of the normal microbiota are also known to cause disease.

Answer: TRUE

2) Open-reading frames are segments of DNA in which both start and stop codons are found.

Answer: TRUE

2) Testing the effectiveness of a new drug for anthrax would be best performed as an experimental study.

Answer: TRUE

2) Two distinguishing factors of the epsilonproteobacteria that they are motile and microaerophilic.

Answer: TRUE

3) As molecular techniques improve, scientists are finding it necessary to reclassify some genera.

Answer: TRUE

3) Cercariae, metacercaria, redia, and sporocysts are all life cycle stages of trematodes.

Answer: TRUE

3) In a completed Gram stain, gram-positive bacteria are purple.

Answer: TRUE

3) In general, ATP is generated in catabolic pathways and expended in anabolic pathways.

Answer: TRUE

3) Maturation of stem cells into mature blood cells occurs in the red bone marrow.

Answer: TRUE

3) The M protein enhances the virulence of Streptococcus by preventing phagocytosis.

Answer: TRUE

3) The thermal death time is the time needed to kill all the bacteria in a particular culture at a certain temperature.

Answer: TRUE

3) The water from tertiary sewage treatment can be used as drinking water.

Answer: TRUE

4) Agar is used as a solidifying agent in microbiological media since few bacteria can degrade it.

Answer: TRUE

4) An apoenzyme that loses its coenzyme subunit will be non-functional.

Answer: TRUE

4) Anton van Leeuwenhoek was the first microbiologist to use a microscope to examine environmental samples for the presence of microorganisms.

Answer: TRUE

4) Due to its target, rifamycins can be effective over a broad spectrum.

Answer: TRUE

4) Mutations that are harmful to cells occur more frequently than those that benefit cells.

Answer: TRUE

4) Pseudomonas has been found growing in quaternary ammonium compounds (quats).

Answer: TRUE

4) Small, hydrophobic molecules pass through a cell membrane most easily by diffusion.

Answer: TRUE

4) The purpose of tertiary sewage treatment is to remove all of the phosphorus, nitrogen, and BOD left from secondary treatment.

Answer: TRUE

5) Both trimethoprim and sulfamethoxazole inhibit reactions along the same metabolic pathway.

Answer: TRUE

5) Cytokine storms negatively impact human health.

Answer: TRUE

5) Histamine and kinins cause increased blood flow and capillary permeability.

Answer: TRUE

5) Laboratory cultivation of obligate anaerobes requires reducing media or special growth chambers filled with inert gases.

Answer: TRUE

5) Moist heat destroys organisms by denaturing proteins.

Answer: TRUE

5) Positive sense RNA strands of viruses are treated like mRNA inside the host cell.

Answer: TRUE

5) Pure cultures of the same species are not always identical in all ways.

Answer: TRUE

5) Some species of dinoflagellates produce neurotoxins that cause fish kills and red tides.

Answer: TRUE

5) Spheroplasts, protoplasts, and mycoplasms are bacterial cells without cell walls.

Answer: TRUE

5) The Limulus amoebocyte assay is used to detect minute amounts of endotoxin in drugs and medical devices.

Answer: TRUE

5) The deinococci can be categorized as extremophiles.

Answer: TRUE

5) The limit of resolution of the compound microscope illuminated with visible light is approximately 0.2 μm.

Answer: TRUE

6) Aspirin alleviates pain, inflammation, and fever by inhibiting prostaglandins.

Answer: TRUE

6) Both phase-contrast microscopy and differential interference contrast microscopy are used to view the internal structures of cells without staining.

Answer: TRUE

6) Both the cellular slime molds and the plasmodial slime molds are members of the phylum Amoebozoa.

Answer: TRUE

6) Cytopathic effects, such as inclusion bodies and syncytium formation, are the visible signs of viral infections.

Answer: TRUE

6) Dogs do not get measles because their cells lack the correct receptor sites for that virus.

Answer: TRUE

6) Glycolysis is utilized by cells in both respiration and fermentation.

Answer: TRUE

6) Microbes are associated with life-sustaining benefits as well as life-threatening diseases.

Answer: TRUE

6) Some antimicrobial chemicals are considered to be disinfectants and antiseptics.

Answer: TRUE

7) A host is not considered diseased until an infection changes one's state of health.

Answer: TRUE

7) Both base substitution and frameshift mutations can result in the formation of premature stop codons.

Answer: TRUE

7) Carbon fixation occurs during the light-independent phase of photosynthesis.

Answer: TRUE

7) Cells viewed in darkfield microscopy appear similar to those stained with the negative stain.

Answer: TRUE

7) Ergot and aflatoxin are toxins sometimes found in grains contaminated with fungi.

Answer: TRUE

7) The internal structure of eukaryotic cilia and flagella are the same.

Answer: TRUE

7) The majority of bacterial species on Earth have not been successfully cultivated.

Answer: TRUE

8) Both respiration and photosynthesis require the use of an electron transport chain.

Answer: TRUE

8) Community-acquired MRSA is typically more virulent than health care-associated MRSA.

Answer: TRUE

8) In the Ames test, any colonies that form on the control should be the result of spontaneous mutations.

Answer: TRUE

8) Microorganisms in deep-sea vents and caves serve as autotrophic primary producers in the absence of sunlight.

Answer: TRUE

8) Serological testing is used for screening bacterial isolates for similarities.

Answer: TRUE

8) The sporozoite, merozoite, gametocyte, and ring stages are all part of the Plasmodium life cycle.

Answer: TRUE

8) Turbidity is an indirect measurement of bacterial growth that can be measured using a spectrophotometer.

Answer: TRUE

9) A segmented genome can result in antigenic shift.

Answer: TRUE

9) An example of a TLR would be peptidoglycan found in the cell wall of gram-positive bacteria.

Answer: TRUE

9) Antiviral drugs target viral processes that occur during viral infection.

Answer: TRUE

9) Autoclaving is the most effective method of moist heat sterilization.

Answer: TRUE

9) Currently, no members of Archaea have been linked to human disease.

Answer: TRUE

9) Filtration methods are used to count bacteria present in very low concentrations, such as in lakes and streams.

Answer: TRUE

9) Infections with some viruses may induce chromosomal changes that alter the growth properties of host cells.

Answer: TRUE

9) The implementation of vaccinations occurred prior to experimental support for the germ theory of disease.

Answer: TRUE

9) Urinary tract infections are the most common forms of nosocomial infections.

Answer: TRUE

"Pox" is a term synonymous with which of the following? a) a macule b) a pustule c) a whitlow d) a vesicle e) a papule

B

A child has a rash on the face, arms, upper legs and torso that is splotchy, and intensifies after being in the sun. The child does not complain of fever or itchiness. The signs and symptoms are consistent with a) cat scratch disease b) fifth disease c) roseola d) chickenpox e) scabies

B

Petechiae are subcutaneous hemorrhages associated with which of the following? a) smallpox b) RMSF c) anthrax d) necrotizing fasciitis e) herpes gladiatorum

B

Some strains of Papillomavirus are oncogenic due to their ability to a) produce deoxyribonucleases b) integrate into the host cell DNA c) escape the phagosome before lysosome fusion d) lie dormant in cells for years e) cause extensive damage to blood vessels

B

Staphylococcal scalded skin syndrome is caused by a) coagulase b) exfoliative toxins c) beta-lactamase d) staphylokinase e) lipase

B

Which of the following is a complication that may result from a Streptococcus pyogenes skin infection? a) scalded skin syndrome b) erysipelas c) a carbuncle d) shingles e) a sty

B

Assume that your lab partner swabs the side of his face and used the swab to inoculate a nutrient agar plate. The next day, he performs a Gram stain on the colonies. They are gram-positive cocci. You advise him that he should next look for A) An acid-fast reaction. B) A coagulase reaction. C) Conidiospores. D) Pseudohyphae. E) Pseudopods.

B) A coagulase reaction.

Most bacteria associated with the teeth and gums are A) Aerobes. B) Anaerobes. C) Facultative anaerobes. D) None of the above.

B) Anaerobes.

On June 30, a 47-year-old man was hospitalized with dizziness, blurred vision, slurred speech, difficulty swallowing, and nausea. Examination revealed facial paralysis. The patient had partially healed superficial knee wounds incurred while laying cement. Cultures taken from the knee wounds should be incubated A) Aerobically. B) Anaerobically. C) In 5-10% CO 2. D) In animal cell culture. E) Any of the above will work.

B) Anaerobically.

11) The treatment for tetanus is A) Penicillin. B) Antibodies. C) Toxoid. D) Cleansing the wound. E) There is no treatment.

B) Antibodies.

On October 5, a pet store sold a kitten that subsequently died. On October 22, rabies was diagnosed in the kitten. Between September 19 and October 23, the pet store had sold 34 kittens. Approximately 1000 people responded to health-care providers following local media alerts. These people were given A) Antibiotics. B) Antirabies immunoglobulin. C) Rabies vaccination. D) Serological tests for rabies. E) Treatment if they tested positive.

B) Antirabies immunoglobulin.

Which of the following pairs is not correctly matched? A) Tetanus blocks relaxation nerve impulse B) Botulism stimulates transmission of nerve impulse C) Poliomyelitis kills CNS cells D) Rabies virus grows in brain cells E) None of the above

B) Botulism stimulates

Arthropods can serve as a reservoir for which of the following diseases? A) Plague B) Brucellosis C) Epidemic typhus D) Yellow fever E) Malaria

B) Brucellosis

A characteristic symptom of plague is A) Small red spots on the skin. B) Bruises on the skin. C) Rose-colored spots. D) Recurrent fever. E) None of the above.

B) Bruises on the skin.

ʺRice water stoolsʺ are characteristic of A) Salmonellosis. B) Cholera. C) Bacillary dysentery. D) Amebic dysentery. E) Tapeworm infestation.

B) Cholera.

Inhalation of arthroconidia is responsible for infection by which of the following organisms? A) Blastomyces B) Coccidioides C) Mycoplasma D) Streptococcus E) None of the above

B) Coccidioides

Microscopic examination of a lung biopsy shows spherules. What is the etiology? A) Blastomyces B) Coccidioides C) Histoplasma D) Mycobacterium E) Pneumocystis

B) Coccidioides

Which of the following is not an intracellular parasite? A) Chlamydophila B) Coccidioides C) Coxiella D) Influenzavirus E) RSV

B) Coccidioides

Which one of the following produces the most potent exotoxin? A) Bordetella pertussis B) Corynebacterium diphtheriae C) Mycobacterium tuberculosis D) Streptococcus pyogenes E) None of the above

B) Corynebacterium diphtheriae

Which one of the following is an irregular, gram-positive rod? A) Bordetella pertussis B) Corynebacterium diptheriae C) Myobacterium tuberculosis D) Streptococcus pyogenes E) None of the above

B) Corynebacterium diptheriae

Which of the following is not acquired by ingestion? A) Botulism B) Cryptococcosis C) Listeriosis D) Poliomyelitis E) None of the above

B) Cryptococcosis

Feces from a patient with diarrhea lasting for weeks with frequent, watery stools should be examined for A) Bacillus cereus. B) Cyclospora. C) Salmonella. D) Vibrio vulnificus. E) Yersinia enterocolitica.

B) Cyclospora.

Which of the following can be transmitted from an infected mother to her fetus across the placenta? A) Borrelia B) Cytomegalovirus C) Spirillum D) Toxoplasma E) Yersinia

B) Cytomegalovirus

Which of the following produces a permanent carrier state following infection? A) Borrelia B) Cytomegalovirus C) Spirillum D) Toxoplasma E) Yersinia

B) Cytomegalovirus

A patient complains of fever, severe muscle and joint pain, and a rash. The patient reports returning from a Caribbean vacation one week ago. Which one of the following do you suspect? A) Bolivian hemorrhagic fever B) Dengue C) Hantavirus hemorrhagic fever D) Typhus E) Yellow fever

B) Dengue

Which of the following diseases has a cutaneous form, especially in individuals over 30 years of age? A) Coccidioidomycosis B) Diphtheria C) Legionellosis D) Scarlet fever E) None of the above

B) Diphtheria

A diagnosis of rabies is confirmed by A) Gram stain. B) Direct fluorescent-antibody test. C) Patientʹs symptoms. D) Passive agglutination. E) Patientʹs death.

B) Direct fluorescent-antibody test.

A vaccine to provide active immunity to serum hepatitis is being prepared from A) Viruses grown in tissue culture. B) Genetically-modified yeast. C) Pooled gamma globulin. D) Viruses grown in embryonated eggs. E) None of the above.

B) Genetically-modified yeast.

Which of the following is diagnosed by the presence of flagellates in the patientʹs feces? A) Cyclospora infection B) Giardiasis C) Trichinellosis D) Cholera E) Cryptosporidiosis

B) Giardiasis

All of the following are required for tooth decay except A) Sucrose. B) Glucose. C) Capsule-forming bacteria. D) Acid-producing bacteria. E) None of the above.

B) Glucose.

Which of the following organisms is most likely to be responsible for periodontal disease? A) Gram-positive cocci B) Gram-positive rods C) Gram-negative cocci D) Gram-negative rods E) Gingivirus

B) Gram-positive rods

The patient is suffocating due to an inflamed epiglottis. What is the etiology? A) Corynebacterium B) Haemophilus C) Bordetella D) Mycobacterium E) Canʹt tell

B) Haemophilus

The etiologic agent of chickenpox. A) Herpes simplex B) Herpes zoster C) HHV-6 D) Parvovirus E) Poxvirus

B) Herpes zoster

Mycoplasmal pneumonia differs from viral pneumonia in that A) It doesnʹt have any known etiologic agent. B) It is treated with tetracyclines. C) Viral pneumonia is treated with tetracyclines. D) The symptoms are distinctly different. E) None of the above.

B) It is treated with tetracyclines.

Which of the following pairs is mismatched? A) Pustular rash smallpox B) Koplik spots rubella C) Papular rash measles D) Vesicular rash chickenpox E) None of the above

B) Koplik spots rubella

Which of the following statements is not true? A) The lepromin test is positive during tuberculoid leprosy. B) Leprosy is highly contagious. C) Loss of nerve sensation occurs in tuberculoid leprosy. D) Disfiguring nodules and deformation occur in lepromatous leprosy. E) Spontaneous recovery occurs in tuberculoid and borderline leprosy.

B) Leprosy is highly contagious.

Microscopic examination of cerebrospinal fluid reveals gram-positive rods. What is the organism? A) Haemophilus B) Listeria C) Naegleria D) Neisseria E) Streptococcus

B) Listeria

A 62-year-old man was hospitalized with an 8-day history of fever, chills, sweats, and vomiting. His temperature on admission was 40°C. A routine peripheral blood smear revealed ring-shaped bodies in the RBCs. What treatment would you prescribe? A) Hyperbaric oxygen B) Mefloquine C) No treatment D) Penicillin E) Streptomycin

B) Mefloquine

The patient has scaling skin on his fingers. Conidiospores are seen in microscopic examination of skin scrapings. A) Candida B) Microsporum C) P. aaeruginosa D) S. aureus E) Scabies

B) Microsporum

Which 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) Travelerʹs diarrhea

B) Mumps

Which of the following causes an infection of the respiratory system that is transmitted by the gastrointestinal route? A) Streptococcus pyogenes B) Mycobacterium tuberculosis C) Mycoplasma pneumoniae D) Haemophilus influenzae E) Streptococcus pneumoniae

B) Mycobacterium tuberculosis

Which of the following vaccines is a cause of the disease it is designed to prevent? A) Tetanus toxoid vaccine B) Oral polio vaccine C) Inactivated polio vaccine D) Haemophilus influenzae capsule vaccine

B) Oral polio vaccine

A 17-year-old male has pus-filled cysts on his face and upper back. Microscopic examination reveals gram-positive rods. This infection is A) Acne. B) Boils. C) Carbuncles. D) Impetigo. E) Pimples.

A) Acne.

Legionella is transmitted by A) Airborne transmission. B) Foodborne transmission. C) Person-to-person contact. D) Fomites. E) Vectors.

A) Airborne transmission.

A patient presents with inflammation of the heart valves, fever, malaise, and subcutaneous nodules at joints; the recommended treatment is A) Anti-inflammatory drugs. B) Streptomycin. C) Chloroquine. D) Hyperbaric chamber. E) Praziquantel.

A) Anti-inflammatory drugs.

Which region of the skin supports the largest bacterial population? A) Axilla B) Scalp C) Forearms D) Legs E) All are equal

A) Axilla

A 1-year-old female was hospitalized with fever, lethargy, and rash. Gram -negative, oxidase-positive cocci were cultured from her cerebrospinal fluid. All of the following are true about the microbe responsible for her symptoms except it may A) Be normal in the cerebrospinal fluid. B) Be normal in the throat. C) Be treated with antibiotics. D) Cause epidemics. E) None of the above.

A) Be normal in the cerebrospinal fluid.

Infection by which of the following begins in lungs and spreads to skin? A) Blastomyces B) Coccidioides C) Histoplasma D) Mycobacterium E) Pneumocystis

A) Blastomyces

A patient has a paroxysmal cough and mucus accumulation. What is the etiology of the symptoms? A) Bordetella B) Corynebacterium C) Klebsiella D) Mycobacterium E) Mycoplasma

A) Bordetella

Which one of the following causes a disease characterized by the catarrhal, paroxysmal, and convalescent stages? A) Bordetella pertussis B) Corynebacterium diphtheriae C) Mycobacterium tuberculosis D) Streptococcus pyogenes E) None of the above

A) Bordetella pertussis

A patient has pneumonia. Gram-negative rods are cultured on nutrient agar from a sputum sample. The etiology is A) Burkholderia pseudomallei B) Chlamydophila psittaci C) Haemophilus influenzae D) Legionella pneumophila E) Streptococcus pneumonia

A) Burkholderia pseudomallei

Microscopic examination of a patientʹs fecal culture shows spiral bacteria. The bacteria probably belong to the genus A) Campylobacter. B) Escherichia. C) Salmonella. D) Shigella. E) Vibrio.

A) Campylobacter.

A 35-year-old female has a red, raised rash on the inside of her thighs. Gram -stained skin scrapings show large budding cells with pseudohyphae. The infection is caused by A) Candida albicans. B) Herpes simplex virus. C) Staphylococcus aureus. D) Streptococcus pyogenes. E) Varicella-zoster virus.

A) Candida albicans.

Which of the following pairs is mismatched? A) Cat-scratch disease malignant pustule developing into septicemia B) Brucellosis a temperature of 40°C each evening C) Tularemia a localized infection appearing as a small ulcer D) Borrelia rash and flulike E) Toxoplasmosis congenital brain damage

A) Cat-scratch disease malignant pustule developing into septicemia

An 8-year-old female has scabs and pus-filled vesicles on her face and throat. Three weeks earlier she had visited her grandmother who had shingles. What infection does the 8 -year-old have? A) Chickenpox B) Measles C) Fever blisters D) Scabies E) German measles

A) Chickenpox

Which of the following is incorrectly matched? A) Chickenpox Poxvirus B) Conjunctivitis Chlamydia trachomatis C) Conjunctivitis Pseudomonas D) Infected tissue fluoresces Dermatomycosis E) Opportunistic infection in AIDS patients Candidiasis

A) Chickenpox Poxvirus

A 30-year-old female was hospitalized after she experienced convulsions. On examination, she was alert and oriented and complained of a fever, headache, and stiff neck. Her symptoms could be due to all of the following except A) Clostridium botulinum. B) Listeria monocytogenes. C) Naegleria fowleri. D) Streptococcus pneumoniae. E) None of the above.

A) Clostridium botulinum.

All of the following are gram-negative rods that cause gastroenteritis except A) Clostridium. B) Escherichia. C) Salmonella. D) Shigella. E) Yersinia.

A) Clostridium.

Which of the following is not a characteristic used to identify S. pyogenes? A) Coagulase-positive B) Group A cell wall antigen C) Group M proteins D) Beta-hemolytic E) None of the above

A) Coagulase-positive

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.

A) Contamination of food during preparation.

The easiest way to prevent outbreaks of gram-negative gastroenteritis is to A) Cook foods thoroughly. B) Salt foods. C) Add vinegar and spices to foods. D) Refrigerate foods. E) All of the above.

A) Cook foods thoroughly.

The patient is suffocating due to the accumulation of dead tissue and fibrin in her throat. What is the etiology? A) Corynebacterium B) Haemophilus C) Bordetella D) Mycobacterium E) Canʹt tell

A) Corynebacterium

Herpes gladiatorium is transmitted by A) Direct contact. B) The respiratory route. C) The fecal-oral route. D) Insect bites. E) All of the above.

A) Direct contact.

A possible complication of herpetic keratitis is A) Encephalitis. B) Fever blisters. C) Subacute sclerosing panencephalitis. D) Congenital rubella syndrome. E) None of the above.

A) Encephalitis.

EB virus causes all of the following except A) Endocarditis. B) Infectious mononucleosis. C) Burkittʹs lymphoma. D) Nasopharyngeal carcinoma. E) None of the above.

A) Endocarditis.

Which of the following is the usual cause of septic shock? A) Endotoxin B) Exotoxin C) Lymphangitis D) Septicemia E) None of the above

A) Endotoxin

Cytoplasmic inclusions were observed in a fetus that died in utero after 6 monthsʹ gestation. The probable cause of the fetusʹs death was A) Fifth disease. B) Herpes simplex. C) Measles. D) Staphylococcus aureus. E) Streptococcus pyogenes.

A) Fifth disease.

Scabies is transmitted by A) Fomites. B) Food. C) Water. D) Soil. E) None of the above.

A) Fomites.

A predisposing factor for infection by Clostridium perfringens is A) Gangrene. B) Burns. C) Debridement. D) Hyperbaric treatment. E) An infected finger.

A) Gangrene.

A 30-year-old female was hospitalized after she experienced convulsions. On examination, she was alert and oriented and complained of a fever, headache, and stiff neck. Which of the following is most likely to provide rapid identification of the cause of her symptoms? A) Gram stain of cerebrospinal fluid B) Gram stain of throat culture C) Biopsy of brain tissue D) Check serum antibodies E) None of the above; it canʹt be diagnosed

A) Gram stain of cerebrospinal fluid

Which of the following is not a characteristic of P. aeruginosa? A) Gram-positive rods B) Oxidative metabolism C) Oxidase positive D) Produce pyocyanin E) None of the above

A) Gram-positive rods

Microscopic examination of cerebrospinal fluid reveals gram-negative rods. What is the organism? A) Haemophilus B) Listeria C) Naegleria D) Neisseria E) Streptococcus

A) Haemophilus

The etiologic agent of fever blisters. A) Herpes simplex B) Herpes zoster C) HHV-6 D) Parvovirus E) Poxvirus

A) Herpes simplex

Which of the following microorganisms causes symptoms most like tuberculosis? A) Histoplasma B) Coccidioides C) Legionella D) Mycoplasma E) Influenzavirus

A) Histoplasma

Which of the following pairs is not correctly matched? 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 parasiteʹs eggs E) Hookworm infestation parasite bores through skin

A) Hydatid disease humans are the definitive host

All of the following statements about puerperal sepsis are true except A) It is transmitted from mother to fetus. B) It is caused by health-care personnel. C) It begins as a focal infection. D) It is a complication of abortion or childbirth. E) It doesnʹt occur anymore because of antibiotics and aseptic techniques.

A) It is transmitted from mother to fetus.

The prodromal symptom(s) of meningitis is (are) A) Like a mild cold. B) Fever and headache. C) Stiff neck and back pains. D) Convulsions. E) Paralysis.

A) Like a mild cold.

The etiologic agent of warts is A) Papovavirus. B) Poxvirus. C) Herpesvirus. D) Parvovirus E) None of the above.

A) Papovavirus.

Which of the following is an opportunistic pathogen? A) Pneumocystis B) Legionella C) Histoplasma D) Mycoplasma E) Rhinovirus

A) Pneumocystis

Which of the following is not transmitted by ingestion? A) Poliomyelitis B) Listeriosis C) Botulism D) Meningococcal meningitis E) Creutzfeldt-Jakob disease

A) Poliomyelitis

Which of the following is not a zoonosis? A) Puerperal sepsis B) Hantavirus infection C) Anthrax D) Brucellosis E) Tularemia

A) Puerperal sepsis

Which of the following is not normal microbiota of the skin? A) Streptococcus B) Pityrosporum C) Staphylococcus D) Propionibacterium E) Corynebacterium

A) Streptococcus

Treatment for tetanus in an immunized person is A) Tetanus toxoid. B) Tetanus immune globulin. C) Penicillin. D) DTP. E) None of the above.

A) Tetanus toxoid.

Typhoid fever differs from salmonellosis in that in typhoid fever A) The microorganisms become invasive. B) The symptoms are due to an exotoxin. C) The symptoms are due to infection of the gallbladder. D) The classic symptom is diarrhea. E) Chemotherapy is highly effective.

A) The microorganisms become invasive.

Which of the following is not transmitted in raw milk? A) Toxoplasmosis B) Anthrax C) Brucellosis D) Listeriosis E) None of the above

A) Toxoplasmosis

Which of the following is evidence that the arthritis afflicting children in Lyme, Connecticut, was due to bacterial infection? A) Treatable with penicillin B) Not contagious C) Accompanied by a rash D) Affected mostly children E) All of the above

A) Treatable with penicillin

Which of the following diseases is not correctly matched to its vaccine? A) Tuberculosis toxoid B) Whooping cough heat-killed bacteria C) Diphtheria toxoid D) Influenza viruses grown in embryonated eggs E) None of the above

A) Tuberculosis toxoid

1) Penicillin was considered a "miracle drug" for all of the following reasons EXCEPT A) it was the first antibiotic. B) it does not affect eukaryotic cells. C) it inhibits gram-positive cell wall synthesis. D) it has selective toxicity. E) it kills bacteria.

Answer: A

1) 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.

Answer: A

1) Which of the following statements regarding fungi is FALSE? A) Most fungi are pathogenic for humans. B) Fungi are eukaryotic heterotrophs. C) Fungi reproduce by forming asexual or sexual spores. D) Most fungi grow well in acidic culture condition. E) Fungi tolerate low moisture conditions.

Answer: A

10) An agent used to reduce the number of bacteria on a toilet would most accurately be called a(n) A) disinfectant. B) antiseptic. C) aseptic. D) fungicide. E) virucide.

Answer: A

10) An enzyme produced in response to the presence of a substrate is called a(n) A) inducible enzyme. B) repressible enzyme. C) restriction enzyme. D) operator. E) promoter.

Answer: A

10) Cytopathic effects are changes in host cells due to A) viral infections. B) protozoan infections. C) fungal infections. D) bacterial infections. E) helminthic infections.

Answer: A

10) Simple staining is often necessary to improve contrast in which microscope? A) compound light microscope B) phase-contrast microscope C) darkfield microscope D) fluorescence microscope E) electron microscope

Answer: A

12) The addition of which of the following to a culture medium will neutralize acids? A) buffers B) sugars C) pH D) heat E) carbon

Answer: A

12) Viruses are not considered living organisms because they A) cannot reproduce by themselves. B) are structurally very simple. C) can only be visualized using an electron microscope. D) typically associated with disease. E) are ubiquitous in nature.

Answer: A

12) Which of the following bacteria is gram-negative? A) Treponema B) Corynebacterium C) Bacillus D) Staphylococcus E) Mycobacterium

Answer: A

12) Which of the following is found normally in serum? A) complement B) interferon C) histamine D) leukocytosis-promoting factor E) TLRs

Answer: A

13) Each of the following is an effect of complement activation EXCEPT A) interference with viral replication. B) bacterial cell lysis. C) opsonization. D) increased phagocytic activity. E) increased blood vessel permeability.

Answer: A

13) NH3 → NO2- A) takes place under aerobic conditions. B) takes place under anaerobic conditions. C) The amount of oxygen does not make any difference.

Answer: A

13) The infectious agent that causes AIDS is a A) virus. B) bacterium. C) yeast. D) protozoan. E) mold.

Answer: A

14) A strictly fermentative bacterium produces energy A) by glycolysis only. B) by aerobic respiration only. C) by fermentation or aerobic respiration. D) only in the absence of oxygen. E) only in the presence of oxygen.

Answer: A

14) Antibiotics that target cell wall synthesis ultimately cause bacterial cell death as a result of A) osmotic lysis. B) inhibition of molecular transport. C) decreased synthesis of peptidoglycan. D) plasmolysis. E) cell shrinkage.

Answer: A

14) Bioremediation of petroleum A) takes place under aerobic conditions. B) takes place under anaerobic conditions. C) The amount of oxygen does not make any difference.

Answer: A

14) Plasma cells are activated by a(n) A) antigen. B) T cell. C) B cell. D) memory cell. E) APC.

Answer: A

14) The term aerotolerant anaerobe refers to an organism that A) does not use oxygen but tolerates it. B) is killed by oxygen. C) uses oxygen or grows without oxygen. D) requires less oxygen than is present in air. E) requires more oxygen than is present in air.

Answer: A

14) Which of the following antimicrobial agents is recommended for use against fungal infections? A) amphotericin B B) bacitracin C) cephalosporin D) penicillin E) polymyxin

Answer: A

14) Which of the following is NOT a domain in the three-domain system? A) animalia B) archaea C) bacteria D) eukarya

Answer: A

14) Which of the following is an effect of opsonization? A) increased adherence of phagocytes to microorganisms B) increased margination of phagocytes C) increased diapedesis of phagocytes D) inflammation E) cytolysis

Answer: A

15) All of the following substances are effective against nonenveloped viruses EXCEPT A) alcohol. B) chlorine. C) ethylene oxide. D) ozone. E) None of the answers is correct; all of these are equally effective against nonenveloped viruses.

Answer: A

15) Bacteria are a commonly used organism for studies of genetic material in the research laboratory. The nucleic acids must first be isolated from the cells for these studies. Which of the following would most likely be used to lyse the bacterial cells for nucleic acid isolation? A) lysozyme B) polymixins C) alcohol D) water E) mycolic acid

Answer: A

16) Archaea differ from bacteria in that archaea A) have diverse cell wall compositions. B) lack nuclei. C) use organic compounds for food. D) reproduce by binary fission. E) are prokaryotic.

Answer: A

7) All of the following are true about leprosy except A) It is rarely fatal. B) Patients with leprosy must be isolated. C) It is transmitted by direct contact. D) Diagnosis may be based on the lepromin test. E) None of the above.

B) Patients with leprosy must be isolated.

17) 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.

Answer: A

17) Who is credited with first observing cells? A) Robert Hooke B) Anton van Leeuwenhoek C) Robert Koch D) Louis Pasteur E) Carolus Linnaeus

Answer: A

18) All of the following organisms produce exotoxins EXCEPT A) Salmonella typhi. B) Clostridium botulinum. C) Corynebacterium diphtheriae. D) Clostridium tetani. E) Staphylococcus aureus.

Answer: A

18) In addition to IgG, the antibodies that can fix complement are A) IgM. B) IgA. C) IgD. D) IgE. E) None of the answers is correct.

Answer: A

18) Protists are a diverse group of organisms that are similar in A) rRNA sequences. B) metabolic type. C) motility. D) ecology. E) None of the answers is correct.

Answer: A

18) To date, most of our natural antibiotics have been found to be produced by members of what genus? A) Streptomyces B) Bacillus C) Penicillium D) Paenibacillus E) Cephalosporium

Answer: A

19) Escherichia coli belongs to the A) proteobacteria. B) gram-positive bacteria. C) green sulfur bacteria. D) spirochetes. E) actinomycetes.

Answer: A

19) Which of the following correctly traces the path of light through the compound microscope? A) light source; condenser; specimen; objective lens; ocular lens B) condenser; light source; specimen; ocular lens; objective lens C) light source; specimen; condenser; objective lens; ocular lens D) condenser; light source; specimen; objective lens; ocular lens E) light source; condenser; objective lens; specimen; ocular lens

Answer: A

2) 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.

Answer: A

2) Which of the following best describes the pattern of microbial death? A) The cells in a population die at a constant rate. B) All the cells in a culture die at once. C) Not all of the cells in a culture are killed. D) The pattern varies depending on the antimicrobial agent. E) The pattern varies depending on the species.

Answer: A

2) Which of the following organisms is using sulfur as a source of energy? A) Thiobacillus: H2S → S0 B) Desulfovibrio: SO42- → H2S C) Proteus: Amino acids → H2S D) Redwood tree: SO42- → Amino acids E) Photosynthetic bacteria: H2S → S0

Answer: A

20) The arrangement of organisms into taxa A) shows degrees of relatedness between organisms. B) shows relationships to common ancestors. C) was designed by Charles Darwin. D) is arbitrary. E) is based on evolution.

Answer: A

20) The most abundant class of antibodies in serum is A) IgG. B) IgM. C) IgA. D) IgD. E) IgE.

Answer: A

21) Symptoms of disease differ from signs of disease in that symptoms A) are changes felt by the patient. B) are changes observed by the physician. C) are specific for a particular disease. D) always occur as part of a syndrome. E) None of the answers is correct.

Answer: A

21) The arguments supporting spontaneous generation were finally disproved by A) Louis Pasteur. B) Francesco Redi. C) Rudolf Virchow. D) John Needham. E) Lazzaro Spallanzani.

Answer: A

Which of the following pairs is mismatched? A) Leprosy direct contact B) Poliomyelitis respiratory route C) Meningococcal meningitis respiratory route D) Rabies direct contact E) None of the above

B) Poliomyelitis respiratory route

Which of the following pairs is mismatched? A) Epiglottitis Haemophilus B) Q fever Rickettsia C) Psittacosis Chlamydia D) Whooping cough Bordetella E) None of the above

B) Q fever Rickettsia

Acute gastroenteritis that occurs after an incubation period of 2 to 3 days is probably caused by A) Giardia B) Rotavirus C) Salmonella D) Staphylococcus aureus E) Trichinella

B) Rotavirus

22) Which of the following best defines a strain? A) a pure culture that is not totally identical to other cultures of the same species B) a group of organisms with a limited geographical distribution C) a population of cells with similar characteristics D) a group of cells derived from a single parent E) same as a species

Answer: A

23) The microbial process of converting sugars to alcohol is known as A) fermentation. B) pasteurization. C) tyndallization. D) lyophilization. E) alcoholism.

Answer: A

23) Which of the following uses CO2 for carbon and H2 for energy? A) chemoautotroph B) chemoheterotroph C) photoautotroph D) photoheterotroph

Answer: A

24) 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.

Answer: A

24) Which of the following bacteria are responsible for more infections and more different kinds of infections? A) Streptococcus B) Staphylococcus C) Salmonella D) Pseudomonas E) Neisseria

Answer: A

24) Which of the following statements is TRUE? A) There are at least thirty complement proteins. B) All of the complement proteins are constantly active in serum. C) Factors B, D, and P cause cytolysis. D) Complement activity is antigen-specific. E) Complement increases after immunization.

Answer: A

25) Both Beggiatoa and the purple sulfur bacteria use H2S. These bacteria differ in that Beggiatoa A) uses H2S for an energy source. B) uses H2S for a carbon source. C) uses light energy. D) belongs to the gammaproteobacteria. E) is a heterotroph.

Answer: A

25) Protozoan and helminthic diseases are difficult to treat because A) their cells are structurally and functionally similar to human cells. B) they replicate inside human cells. C) they do not have ribosomes. D) they do not reproduce. E) they have more genes than bacteria.

Answer: A

25) The use of phenol (carbolic acid) as a wound disinfectant was first practiced by A) Lister. B) Semmelweis. C) Pasteur. D) Holmes. E) Koch.

Answer: A

25) You are performing a Gram stain on gram-positive bacteria and you stop after the addition of the first dye. What is the appearance of the bacteria at this point? A) purple B) red C) colorless D) brown

Answer: A

26) Bacteriophages derive all of the following from the host cell EXCEPT A) lysozyme. B) tRNA. C) amino acids. D) nucleotides. E) ATP.

Answer: A

26) You are performing a Gram stain on gram-negative bacteria and you stop after the addition of the mordant. What is the appearance of the bacteria at this point? A) purple B) red C) colorless D) brown

Answer: A

27) The alternative pathway for complement activation is initiated by A) lipid-carbohydrate complexes and C3. B) C5C9. C) antigenantibody reactions. D) factors released from phagocytes. E) factors released from damaged tissues.

Answer: A

27) Which of the following statements are true? 1-Electron carriers are located at ribosomes. 2-ATP is a common intermediate between catabolic and anabolic pathways. 3-ATP is used for the long-term storage of energy and so is often found in storage granules. 4-Anaerobic organisms are capable of generating ATP via respiration. 5-ATP can be generated by the flow of protons across protein channels. A) 2, 4, 5 B) 1, 3, 4 C) 2, 3, 5 D) 1, 2, 3 E) All of the statements are true.

Answer: A

28) In which of the following situations would Koch's postulates be utilized? A) determination of the cause of a patient's illness in a hospital microbiology lab B) development of a new antibiotic in a pharmaceutical lab C) determination of the cause of cancer in a patient D) formulation of a vaccine against a new pathogen in a genetic engineering lab E) whenever the scientific method is used to investigate a microbiological problem

Answer: A

28) You are performing a Gram stain on gram-positive bacteria and you stop after the addition of the counterstain. What is the appearance of the bacteria at this point? A) purple B) red C) colorless D) brown

Answer: A

29) Activation of C3a results in A) acute inflammation. B) increased blood vessel permeability. C) opsonization. D) attraction of phagocytes. E) cell lysis.

Answer: A

30) A clone is A) genetically identical cells derived from a single cell. B) a genetically engineered cell. C) a taxon composed of species. D) a mound of cells on an agar medium. E) None of the answers is correct.

Answer: A

30) All of the following bacteria release endotoxin EXCEPT A) Clostridium botulinum. B) Salmonella typhi. C) Neisseria meningitidis. D) Proteus vulgaris. E) Haemophilus influenzae.

Answer: A

30) The CDC is located in A) Atlanta, GA. B) Washington, DC. C) New York City, NY. D) Las Angeles, CA. E) Chicago, IL.

Answer: A

31) The necessary ingredients for DNA synthesis can be mixed together in a test tube. The DNA polymerase is from Thermus aquaticus, and the template is from a human cell. The DNA synthesized would be most similar to A) human DNA. B) T. aquaticus DNA. C) a mixture of human and T. aquaticus DNA. D) human RNA. E) T. aquaticus RNA.

Answer: A

31) Which of the following findings was essential for Edward Jenner's vaccination process? A) Exposure to a milder disease form may produce immunity. B) A weakened microorganism will not cause disease. C) Someone who recovers from a disease will not acquire that disease again. D) Disease is caused by viruses. E) Pathogenic microorganisms infect all humans and animals in the same manner.

Answer: A

32) After ingesting a pathogen, lysosomal enzymes produce all of the following EXCEPT A) complement. B) O2-. C) H2O2. D) OH∙. E) HOCl.

Answer: A

32) Which of the following bacterial components would most likely result in B cell stimulation by T-independent antigens? A) capsule B) flagellum C) pili D) ribosome E) plasmid

Answer: A

33) In the ONPG and MUG test for fecal coliforms, a sample that is positive for E. coli will be A) positive for ONPG; fluorescent in UV light. B) negative for ONPG; fluorescent in UV light. C) positive for ONPG; non-fluorescent in UV light. D) negative for ONPG; non-fluorescent in UV light.

Answer: A

34) A lytic virus has infected a patient. Which of the following would best describe what is happening inside the patient? A) The virus is causing the death of the infected cells in the patient. B) The virus is not killing any cells in the host. C) The virus is incorporating its nucleic acid with that of the patient's cells. D) The virus is slowly killing the patient's cells. E) The virus is infecting cells and then releasing only small amounts of virus.

Answer: A

34) In which of the following diseases can gender be considered a viable predisposing factor? A) urinary tract infections B) pneumonia C) salmonellosis D) tetanus E) anthrax

Answer: A

34) 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.

Answer: A

34) The mechanism by which the presence of glucose inhibits the arabinose operon is A) catabolite repression. B) translation. C) DNA polymerase. D) repression. E) induction.

Answer: A

34) Which of the following destroys virus-infected cells? A) CTL B) Treg C) TH D) dendritic cells E) B cells

Answer: A

34) You have isolated a prokaryotic cell. The first step in identification is a(n) A) Gram stain. B) lactose fermentation test. C) endospore stain. D) flagella stain. E) DNA fingerprint.

Answer: A

35) All of the following substances are used to preserve foods EXCEPT A) biguanides. B) nisin. C) potassium sorbate. D) sodium nitrite. E) calcium propionate.

Answer: A

35) Some viruses, such as human herpesvirus 1, infect a cell without causing symptoms. These are called A) latent viruses. B) lytic viruses. C) phages. D) slow viruses. E) unconventional viruses.

Answer: A

35) Which microscope is used to observe viruses and the internal structure of thinly sectioned cells? A) transmission electron microscope B) darkfield microscope C) fluorescence microscope D) brightfield microscope E) scanning electron microscope

Answer: A

35) Which of the following is a nucleated, unicellular organism that, if you changed the incubation temperature, would form filaments with conidiospores? A) ascomycete B) cellular slime mold C) euglenozoa D) tapeworm E) plasmodial slime mold

Answer: A

36) Cytokines released by TH1 cells A) activate CD8+ cells to CTLs. B) convert TH1 cells to TH2 cells. C) convert TH2 cells to TH1 cells. D) kill parasites. E) convert B cells to T cells.

Answer: A

36) If you knew the sequence of nucleotides within a gene, which one of the following could you determine with the most accuracy? A) the primary structure of the protein B) the secondary structure of the protein C) the tertiary structure of the protein D) the quaternary structure of the protein E) The answer cannot be determined based on the information provided.

Answer: A

37) All of the following pertain to fever EXCEPT that it A) accelerates microbial growth by increasing iron absorption from the digestive tract. B) stimulates T lymphocyte activity. C) is caused by interleukin-1 and TNF-alpha coming into contact with the hypothalamus. D) intensifies the effect of antiviral interferons. E) can be initiated by specific types of pathogens.

Answer: A

38) An enzyme that copies DNA to make a molecule of RNA is A) RNA polymerase. B) DNA ligase. C) DNA helicase. D) transposase. E) DNA polymerase.

Answer: A

39) All of the following are effective for destroying prions EXCEPT A) boiling. B) incineration. C) NaOH + autoclaving at 134°C. D) proteases. E) None of the answers are correct; each of these will destroy prions.

Answer: A

39) Gallionella bacteria can get energy from the reaction Fe2+ → Fe3+. This reaction is an example of A) oxidation. B) reduction. C) fermentation. D) photophosphorylation. E) the Calvin-Benson cycle.

Answer: A

39) The following steps occur during multiplication of retroviruses. Which is the fourth step? A) synthesis of double-stranded DNA B) synthesis of +RNA C) attachment D) penetration E) uncoating

Answer: A

39) Thymic selection A) destroys T cells that do not recognize self-molecules of MHC. B) destroys B cells that make antibodies against self. C) destroys MHC molecules. D) destroys CD4+ cells that attack self. E) activates B cells.

Answer: A

4) A gram-positive bacteria suddenly acquires resistance to the antibiotic methicillin. This trait most likely occurred due to A) conjugation. B) binary fission. C) meisosis. D) transformation. E) transduction.

Answer: A

4) Which of the following is NOT a characteristic of Neisseria? A) requires X and V factors B) cocci C) gram-negative D) oxidase-positive E) Some species are human pathogens.

Answer: A

4) Which of the following is NOT used as a criterion to classify viruses? A) biochemical tests B) morphology C) nucleic acid D) size E) number of capsomeres

Answer: A

41) Bacterial smears are fixed before staining to A) affix the cells to the slide. B) make their walls permeable. C) accept stain. D) make the cells visible.

Answer: A

41) Into which group would you place a multicellular organism that has a mouth and lives inside the human liver? A) Animalia B) Fungi C) Plantae D) Firmicutes (gram-positive bacteria) E) Proteobacteria (gram-negative bacteria)

Answer: A

42) Mebendazole is used to treat cestode infections. It interferes with microtubule formation; therefore, it would NOT affect A) bacteria. B) fungi. C) helminths. D) human cells. E) protozoa.

Answer: A

42) Ringworm is caused by a(n) A) fungus. B) cestode. C) nematode. D) protozoan. E) trematode.

Answer: A

42) Several inherited deficiencies in the complement system occur in humans. Which of the following would be the MOST severe? A) deficiency of C3 B) deficiency of C5 C) deficiency of C6 D) deficiency of C7 E) deficiency of C8

Answer: A

42) Which enzyme catalyzes the reaction: 2H2O2 → 2H2O + O2? A) catalase B) oxidase C) peroxidase D) superoxide dismutase

Answer: A

43) ADCC is a process that is most effective in destroying A) eukaryotic pathogens. B) virus-infected host cells. C) extracellular viruses. D) bacterial pathogens. E) bacterial toxins.

Answer: A

43) Which of the following antibiotics causes misreading of mRNA? A) aminoglycoside changes shape of 30S units B) chloramphenicol inhibits peptide bonds at 50S subunit C) oxazolidinone prevents formation of 70S ribosome D) streptogamin prevents release of peptide from 70S ribosome E) tetracyclines bind with 30S subunit

Answer: A

43) Which of the following are NOT energy reserves? A) carboxysomes B) polysaccharide granules C) lipid inclusions D) sulfur granules E) metachromatic granules

Answer: A

43) Which of the following pairs is NOT correctly matched? A) elementary body & Escherichia B) endospore & Bacillus C) endospore & Clostridium D) heterocyst & cyanobacteria E) myxospore & gliding bacteria

Answer: A

44) The antibiotic actinomycin D binds between adjacent G-C pairs, thus interfering with A) transcription. B) translation. C) cellular respiration. D) plasma membrane function. E) peptide bond formation.

Answer: A

44) Which of the following statements about biofilms is FALSE? A) Compared to free-living bacteria, biofilms are more sensitive to antibiotics. B) Biofilms in pipes can block the flow of water. C) Biofilms in your body protect mucous membranes from harmful microbes. D) Biofilms on medical devices cause infections. E) Biofilms on rocks provide food for animal life.

Answer: A

45) ) In microscopy, the term resolution A) refers to the ability to distinguish fine structure and detail in a specimen. B) is the same as the total magnification of a specimen. C) is improved when longer wavelengths of light are employed. D) is only observed in stained specimens. E) refers to magnification when using the electron microscope.

Answer: A

45) Which one of the following is most resistant to chemical biocides? A) gram-negative bacteria B) gram-positive bacteria C) mycobacteria D) protozoan cysts E) viruses with lipid envelopes

Answer: A

45) 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

Answer: A

5) All of the following contribute to a pathogen's invasiveness EXCEPT A) toxins. B) capsules. C) cell wall components. D) hyaluronidase. E) coagulases.

Answer: A

5) Commercial utilization of microbial products has become increasingly popular due to their environmentally friendly nature. Removal of these products from the environment typically utilizes A) enzymes. B) organic acids. C) organic solvents. D) soap. E) alcohol.

Answer: A

5) TLRs attach to all of the following EXCEPT A) AMPs. B) flagellin. C) LPS. D) PAMPs. E) peptidoglycan.

Answer: A

5) The guano deposited by seabirds is used a source for which of the following fertilizer components? A) phosphate B) nitrate C) sulfate D) carbonate E) potassium

Answer: A

5) Which of the following is NOT a product of transcription? A) a new strand of DNA B) rRNA C) tRNA D) mRNA E) None of the answers are correct; all of these are products of transcription.

Answer: A

5) Which of the following pairs of terms is mismatched? A) bacteriostatic — kills vegetative bacterial cells B) germicide - kills microbes C) virucide - inactivates viruses D) sterilant — destroys all living microorganisms E) fungicide — kills yeasts and molds

Answer: A

5) Which of the following statements regarding lichens is FALSE? A) Lichens are very tolerant to pollution. B) Lichens represent a mutualistic relationship between a fungus and an alga. C) Lichens are often the first life form to colonize rock or soil. D) The algal partner produces carbohydrates that are absorbed by the fungal partner. E) The fungal partner provides a means of attachment and protects the algal partner from desiccation.

Answer: A

6) Adding untreated sewage to a freshwater lake would cause the biochemical oxygen demand to A) increase. B) decrease. C) stay the same. D) The answer cannot be determined based on the information provided.

Answer: A

6) The antimicrobial activity of chlorine is due to which of the following? A) the formation of hypochlorous acid B) the formation of hydrochloric acid C) the formation of ozone D) the formation of a hypochlorite ion E) disruption of the plasma membrane

Answer: A

6) Which of the following diseases is NOT spread by droplet infection?A) botulism B) tuberculosis C) measles D) the common cold E) diphtheria

Answer: A

6) Which of the following statements is NOT a possible outcome of antigen-antibody reaction? A) clonal deletion B) activation of complement C) opsonization D) ADCC E) agglutination

Answer: A

7) The definition of lysogeny is A) phage DNA is incorporated into host cell DNA. B) lysis of the host cell due to a phage. C) the period during replication when virions are not present. D) when the burst time takes an unusually long time. E) attachment of a phage to a cell.

Answer: A

7) Which of the following do you expect to be MOST resistant to high temperatures? A) Bacillus subtilis B) Eschericia coli C) Neisseria gonorrhoeae D) Staphylococcus aureus E) Streptococcocus pyogenes

Answer: A

9) CD4+ T cells are activated by A) interaction between CD4+ and MHC II. B) interaction between TCRs and MHC II. C) cytokines released by dendritic cells. D) cytokines released by B cells. E) complement.

Answer: A

9) Fatty acids are oxidized in A) the Krebs cycle. B) the electron transport chain. C) glycolysis. D) the pentose phosphate pathway. E) the Entner-Doudoroff pathway.

Answer: A

9) The biosafety level (BSL) for most introductory microbiology laboratories is A) BSL-1. B) BSL-2. C) BSL-3. D) BSL-4.

Answer: A

9) Which of the following is NOT a membrane-disrupting toxin? A) A-B toxin B) hemolysin C) leukocidin D) streptolysin O E) streptolysin S

Answer: A

9) Which of the following is NOT associated with viruses? A) organelles B) nucleic acid C) envelope D) spikes E) capsid

Answer: A

9) Which of the following is the best evidence for a three-domain system? A) Nucleotide sequences in ribosomal RNA vary between all three domains. B) There are three distinctly different sets of metabolic reactions. C) There are three distinctly different Gram reactions. D) Some bacteria live in extreme environments. E) There are three distinctly different types of nuclei.

Answer: A

1) All of the following are habitats for extremophiles EXCEPT A) an acid mine wash. B) the Atlantic Ocean. C) inside rock. D) a salt-evaporating pond. E) 100°C water.

Answer: B

1) Innate immunity A) is slower than adaptive immunity in responding to pathogens. B) is nonspecific and present at birth. C) involves a memory component. D) involves T cells and B cells. E) provides increased susceptibility to disease.

Answer: B

10) Which of the following organelles most closely resembles a prokaryotic cell? A) nucleus B) mitochondrion C) Golgi complex D) vacuole E) cell wall

Answer: B

10) You have isolated a bacterium that grows in a medium containing an organic substrate and nitrate in the absence of oxygen. The nitrate is reduced to nitrogen gas. You can be sure that this bacterium is A) gram-positive. B) using anaerobic respiration. C) a chemoautotroph. D) a photoautotroph. E) a photoheterotroph.

Answer: B

11) When glucose is high, cAMP is _____ : CAP _____ bind the lac operator, and RNA polymerase _____ bind the lac promoter. A) high; does; does B) low; does not; does not C) high; does not; does D) low; does not; does E) None of the answers is correct.

Answer: B

11) Which microscope is used to see internal structures of cells in a natural state? A) compound light microscope B) phase-contrast microscope C) darkfield microscope D) fluorescence microscope E) electron microscope

Answer: B

11) Which of the following is the best definition of oxidative phosphorylation? A) Electrons are passed through a series of carriers to O2. B) A proton gradient allows hydrogen ions to flow back into the cells through transmembrane protein channels, releasing energy that is used to generate ATP. C) ATP is directly transferred from a substrate to ADP. D) Electrons are passed through a series of carriers to an organic compound.

Answer: B

11) Which of the following lacks a cell wall? A) Borrelia B) Mycoplasma C) Mycobacterium D) Clostridium E) Nocardia

Answer: B

12) Transformation is the transfer of DNA from a donor to a recipient cell A) by a bacteriophage. B) as naked DNA in solution. C) by cell-to-cell contact. D) by crossing over. E) by sexual reproduction.

Answer: B

12) Which microscope uses visible light? A) confocal microscope B) differential interference contrast microscope C) fluorescence microscope D) scanning acoustic microscope E) scanning electron microscope

Answer: B

12) Which of the following methods of action would be bacteriostatic? A) competitive inhibition with folic acid synthesis B) inhibition of protein synthesis C) injury to plasma membrane D) inhibition of cell wall synthesis E) competitive inhibition with DNA gyrase

Answer: B

12) Which of the following statements regarding protozoa is FALSE? A) Protozoa are unicellular eukaryotes. B) Nearly all protozoa cause disease. C) Most protozoa reproduce asexually. D) Protozoa are common in water and soil. E) Some protozoan pathogens are transmitted by arthropod vectors.

Answer: B

Which of the following pairs is not correctly matched? A) Ergot gangrene B) Salmonella endotoxin coagulates blood C) Vibrio enterotoxin secretion of Cl- , CO32-, and H2O D) Aflatoxin liver cancer E) All of the above

B) Salmonella endotoxin coagulates blood

13) In mid-December, a woman with insulin-dependent diabetes who had been on prednisone fell and received an abrasion on the dorsal side of her right hand. She was placed on penicillin. By the end of January, the ulcer had not healed, and she was referred to a plastic surgeon. On January 30, a swab of the wound was cultured at 35°C on blood agar. On the same day, a smear was made for Gram staining. The Gram stain showed large (10 µm) cells. Brownish, waxy colonies grew on the blood agar. Slide cultures set up on February 1 and incubated at 25°C showed septate hyphae and single conidia. The most likely cause of the infection is a A) gram-negative bacterium. B) dimorphic fungus. C) parasitic alga. D) yeast. E) protozoan.

Answer: B

13) Oxidizing agents include all of the following EXCEPT A) chlorine. B) glutaraldehyde. C) hydrogen peroxide. D) iodine. E) ozone.

Answer: B

13) Which of the following form conidiospores? A) endospore-forming gram-positive rods and cocci B) actinomycetes and related organisms C) rickettsias D) anaerobic gram-negative cocci E) spiral and curved bacteria

Answer: B

15) Which of the following is an advantage of the standard plate count? A) can readily count cells that form aggregates B) determines the number of viable cells C) can be performed on very dilute samples, such as lake water D) provides immediate results E) can be used to count heat-sensitive bacteria

Answer: B

16) For the biogeochemical cycles of the following elements, which does NOT have an atmospheric cycle? A) carbon B) phosphorus C) sulfur D) nitrogen

Answer: B

17) In noncyclic photophosphorylation, O2 is released from A) CO2. B) H2O. C) C6H12O6. D) sunlight. E) chlorophyll.

Answer: B

17) More than half of our antibiotics are A) produced by fungi. B) produced by bacteria. C) synthesized in laboratories. D) produced by Fleming. E) produced by eukaryotic organisms.

Answer: B

17) Which concentration of ethanol is the most effective bactericide? A) 100 percent B) 70 percent C) 50 percent D) 40 percent E) 30 percent

Answer: B

17) Which of the following would be the first step in biosynthesis of a virus with a - (minus) strand of RNA? A) synthesis of DNA from an RNA template B) synthesis of double-stranded RNA from an RNA template C) synthesis of double-stranded RNA from a DNA template D) transcription of mRNA from DNA E) synthesis of DNA from a DNA template

Answer: B

18) An infectious protein is a A) bacteriophage. B) prion. C) retrovirus. D) viroid. E) papovavirus.

Answer: B

18) The swelling associated with inflammation decreases when the fluid A) returns to the blood. B) goes into lymph capillaries. C) is excreted in urine. D) is lost as perspiration. E) is transported into macrophages.

Answer: B

Poultry products are a likely source of infection by A) Staphylococcus aureus. B) Salmonella enterica. C) Vibrio cholera. D) Shigella spp. E) Clostridium perfringens.

B) Salmonella enterica.

Infections by all of the following bacteria may be transmitted by dog or cat bites except A) Pasteurella multocida. B) Streptobacillus. C) Bacteroides. D) Fusobacterium. E) None of the above.

B) Streptobacillus.

18) Which of the following is the best definition of fermentation? A) the partial reduction of glucose to pyruvic acid B) the partial oxidation of glucose with organic molecules serving as electron acceptors C) the complete catabolism of glucose to CO2 and H2O D) the production of energy by oxidative-level phosphorylation E) the production of energy by both substrate and oxidative phosphorylation

Answer: B

18) Who is credited with first observing microorganisms? A) Robert Hooke B) Anton van Leeuwenhoek C) Robert Koch D) Louis Pasteur E) Carolus Linnaeus

Answer: B

19) Biogenesis refers to the A) spontaneous generation of organisms from nonliving matter. B) development of life forms from preexisting life forms. C) development of aseptic technique. D) germ theory of disease.

Answer: B

19) In the scientific name Enterobacter aerogenes, Enterobacter is the A) specific epithet. B) genus. C) family. D) order. E) kingdom.

Answer: B

19) Large antibodies that agglutinate antigens are A) IgG. B) IgM. C) IgA. D) IgD. E) IgE.

Answer: B

19) Which of the following statements about fixed macrophages is FALSE? A) They are found in certain tissues and organs. B) They develop from neutrophils. C) They are cells of the mononuclear phagocytic system. D) They are mature monocytes. E) They gather at sites of infection.

Answer: B

Treatment for tetanus in an unimmunized person is A) Tetanus toxoid. B) Tetanus immune globulin. C) Penicillin. D) DTP. E) None of the above.

B) Tetanus immune globulin.

The most common route of central nervous system invasion by pathogens is through A) The skin. B) The circulatory system. C) The gastrointestinal system. D) The parenteral route. E) Direct penetration into nerves.

B) The circulatory system.

2) Which of the following pairs is mismatched? A) DNA polymerase — makes a molecule of DNA from a DNA template B) RNA polymerase — makes a molecule of RNA from an RNA template C) DNA ligase — joins segments of DNA D) transposase — insertion of DNA segments into DNA E) DNA gyrase — coils and twists DNA

Answer: B

20) Which of the following could be used to sterilize plastic Petri plates in a plastic wrapper? A) autoclave B) gamma radiation C) microwaves D) sunlight E) ultraviolet radiation

Answer: B

20) Which one of the following bacteria does NOT belong with the others? A) Bacillus B) Escherichia C) Lactobacillus D) Staphylococcus E) Streptococcus

Answer: B

21) All of the following are affects of histamine EXCEPT A) vasodilation. B) fever. C) swelling. D) redness. E) pain.

Answer: B

21) An example of a latent viral infection is A) subacute sclerosing panencephalitis. B) cold sores. C) influenza. D) smallpox. E) mumps.

Answer: B

Which of the following is true about the normal microbiota of the nervous system? A) Only transient microbiota are present. B) There are no normal microbiota. C) Normal microbiota are present in the central nervous system only. D) Normal microbiota are present in the peripheral nervous system only. E) None of the above.

B) There are no normal microbiota.

Which of the following is not treated with penicillin? A) Pericarditis B) Tularemia C) Anthrax D) Listeriosis E) None of the above

B) Tularemia

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

B) Vibrio

Which of the following is treated with tetracycline? A) Staphylococcal food poisoning B) Vibrio parahaemolyticus gastroenteritis C) Infectious hepatitis D) Escherichia coli gastroenteritis E) Trichinellosis

B) Vibrio parahaemolyticus gastroenteritis

Epidemics of bacterial infections of the digestive system are transmitted by A) Food. B) Water. C) Milk. D) The respiratory route. E) All of the above.

B) Water.

A child complains of intensely itchy "pimples" on the hands and wrists. The lesions are small inflamed streaks, but do not appear to contain pus. The child's condition may be the result of infection with a) Staphylococcus epidermidis b) Pseudomonas aeruginosa c) Sarcoptes scabiei d) Sporothrix schenkii e) Clostridium perfringens

C

A small puncture wound on a woman's arm has become swollen, hot to the touch, and intensely painful. There is tissue necrosis, but it is not "gassy," and under the microscope Gram-positive cocci in chains are present. Which of the following microbes is likely to be responsible? a) Clostridium perfringens b) Pseudomonas aeruginosa c) Streptococcus pyogenes d) Staphylococcus aureus e) Sporothrix schenckii

C

A specific wavelength of blue light can be used to treat a) bacteremia b) swimmer's ear c) acne d) RMSF e) cat scratch fever

C

Acyclovir is a chemotherapeutic agent used to treat a) measles b) anthrax c) herpes d) acne e) smallpox

C

An infection of a hair follicle at the base of an eyelid is called a a) carbuncle b) furuncle c) sty d) pimple e) macule

C

Cat scratch disease is caused by a) Pseudomonas aeruginosa b) Staphylococcus aureus c) Bartonella henselae d) Streptococcus pyogenes e) Rickettsia rickettsii

C

Clostridium perfringens is a strict anaerobe that is a common environmental contaminant and consequently of wounds due to its ability to a) invade cells b) produce hyaluronidase c) produce endospores d) form biofilms e) grown in an insect vector

C

Normal skin microbiota are able to grow on the skin because of their resistance to a) salt b) sebum, salt, and keratin c) sebum and salt d) sebum e) keratin

C

Transovarian transmission is a process by which a) a pathogen infects the ovaries of its host b) a pathogen is transmitted through the ingestion of contaminated eggs c) an infected female vector transmits a pathogen to the eggs in its ovaries d) a pathogen is spread from host to host by unprotected sexual intercourse e) a pathogen is transmitted from an infected male to a healthy female during mating

C

Ultraviolet illumination is the quickest way to diagnose infections of which of the following? a) Piedraia hortae b) Pseudallescheria c) Malassezia furfur d) Leishmania sp. e) Sarcoptes scabiei

C

Virulent strains of Staphylococcus aureus can resist penicillin because they produce a) a slime layer b) lipase c) beta-lactamase d) coagulase e) staphylokinase

C

What is the pathogenic process underlying Rocky Mountain spotted fever? a) interference with host cell metabolism b) stimulation of a strong immune response c) damage to blood vessels d) formation of biofilms in host tissues e) cellular damage via potent exotoxins

C

Which of the following bacterial pathogens is an intracellular parasite? a) Pseudomonas aeruginosa b) Bacillus anthracis c) Bartonella henselae d) Propionibacterium acnes e) Clostridium perfringens

C

Which of the following can cause birth defects? a) roseola b) smallpox c) rubella d) measles e) chickenpox

C

Which of the following forms of leishmaniasis is typically fatal? a) mucocutaneous b) cutaneous c) visceral d) both cutaneous and mucocutaneous are frequently fatal e) visceral, mucocutaneous, and cutaneous are all potentially fatal

C

Which of the following is (are) not correctly matched? Salk Vaccine 1. Consists of a formalin- inactivated virus 2. Administered orally 3. Requires booster doses Sabin Vaccine 4. Consists of a live, attenuated polio virus 5. Administered orally 6. May cause polio A) 1, 2, and 3 B) 4, 5, and 6 C) 1 and 3 D) 2 E) None of the above

C) 1 and 3

Scabies is a skin disease caused by A) A slow virus. B) A protozoan. C) A mite. D) A bacterium. E) A prion.

C) A mite.

Encephalitis and meningitis are difficult to treat because A) They are not caused by bacteria. B) Antibiotics damage tissues. C) Antibiotics cannot penetrate the blood-brain barrier. D) The infections move along peripheral nerves. E) All of the above.

C) Antibiotics cannot penetrate the blood-brain barrier.

The recurrence of influenza epidemics is due to A) Lack of antiviral drugs. B) The Guillain-Barré syndrome. C) Antigenic shift. D) Lack of naturally acquired active immunity. E) All of the above.

C) Antigenic shift.

Thrush and vaginitis are caused by A) Herpesvirus. B) Chlamydia trachomatis. C) Candida albicans. D) Staphylococcus aureus. E) Streptococcus pyogenes.

C) Candida albicans.

All of the following are true about Group B streptococci except that they A) Are present in healthy carriers. B) Cause gram-positive sepsis. C) Cause strep throat. D) Cause neonatal sepsis. E) None of the above

C) Cause strep throat.

All of the following can be transmitted to humans from domestic cats except A) Toxoplasmosis. B) Plague. C) Chagasʹ disease D) Bartonella. E) None of these diseases is transmitted by cats.

C) Chagasʹ disease

A patient has pus-filled vesicles and scabs on her face, throat, and lower back. She most likely has A) Measles. B) Mumps. C) Chickenpox. D) Rubella. E) Smallpox.

C) Chickenpox.

Meningitis that begins as an infection of the lungs is caused by A) Flavobacterium meningosepticum. B) Streptococcus pneumoniae. C) Cryptococcus neoformans. D) Haemophilus influenzae. E) Neisseria meningitidis.

C) Cryptococcus neoformans.

Which of the following can be treated with topical chemotherapeutic agents? A) Herpes gladiatorium B) Sporotrichosis C) Dermatomycosis D) Rubella E) None of the above

C) Dermatomycosis

Which of the following pairs is incorrectly matched? A) Beef E. coli O157:H7 B) Delicatessen meats Listeria C) Eggs Trichinella D) Milk Campylobacter E) Oysters Vibrio

C) Eggs Trichinella

The most effective control of a vectorborne disease is A) Treatment of infected humans. B) Treatment of infected wild animals. C) Elimination of the vector. D) Avoidance of endemic areas. E) None of the above.

C) Elimination of the vector.

Amoebic dysentery and bacillary dysentery differ in the A) Mode of transmission. B) Appearance of the patientʹs stools. C) Etiologic agent. D) All of the above. E) None of the above.

C) Etiologic agent.

Which of the following pairs is mismatched? A) Rickettsia intracellular parasite B) Brucella gram-negative aerobic rods C) Francisella gram-positive facultatively anaerobic pleomorphic rods D) Bacillus gram-positive endospore-forming rods E) None of the above

C) Francisella gram-positive facultatively anaerobic pleomorphic rods

The etiologic agent of roseola. A) Herpes simplex B) Herpes zoster C) HHV-6 D) Parvovirus E) Poxvirus

C) HHV-6

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

C) Have shorter incubation times.

Which of the following causes an infection of the liver? A) Salmonella B) Shigella C) Hepatitis A virus D) Vibrio E) Escherichia

C) Hepatitis A virus

Which of the viruses listed meets these criteria? Diagnosed by PCR, incubation of 4-22 weeks, transmitted by the parenteral route, it is a flavivirus. A) Hepatitis A virus. B) Hepatitis B virus. C) Hepatitis C virus. D) Hepatitis D virus. E) Hepatitis E virus.

C) Hepatitis C virus.

You are trying to identify the cause of a patientʹs middle ear infection. After 24 hours, there is no growth on blood agar incubated aerobically at 37°C. Your next step is to try again A) Using nutrient agar. B) Incubating at 25°C. C) Incubating anaerobically. D) Incubating at 45°C. E) Then give up.

C) Incubating anaerobically.

All of the following statements about staphylococcal food poisoning are true except A) Suspect foods are those not cooked before eating. B) It can be prevented by refrigeration. C) It can be prevented by boiling foods for 5 minutes before eating. D) It is treated by replacing water and electrolytes. E) It is characterized by rapid onset and short duration of symptoms.

C) It can be prevented by boiling foods for 5 minutes before eating.

8) Which of the following is not transmitted by the respiratory route? A) N. meningitidis B) H. influenzae C) L. monocytogenes D) C. neoformans E) None of the above

C) L. monocytogenes

A patient has the following symptoms: a papule, enlarged lymph nodes. Microscopic examination of the papule reveals nucleated cells in white blood cells. The patient most likely has: A) Anthrax. B) Brucellosis. C) Leishmaniasis. D) Malaria. E) Schistosomiasis.

C) Leishmaniasis.

Helicobacter can grow in the stomach because it A) Hides in macrophages. B) Makes a capsule. C) Makes NH3. D) Makes HCl. E) None of the above.

C) Makes NH3.

Which of the following is not caused by a bacterium? A) Epidemic typhus B) Tickborne typhus C) Malaria D) Plague E) Relapsing fever

C) Malaria

Infection by which of the following results in the formation of Ghon complexes? A) Bordetella pertussis B) Corynebacterium diptheriae C) Mycobacterium tuberculosis D) Streptococcus pyogenes E) None of the above

C) Mycobacterium tuberculosis

Which of the following does not produce an exotoxin? A) Bordetella pertussis B) Corynebacterium diptheriae C) Mycobacterium tuberculosis D) Streptococcus pygones E) None of the above

C) Mycobacterium tuberculosis

Infection by which of the following is often confused with viral pneumonia? A) Blastomyces B) Coccidioides C) Mycoplasma D) Streptococcus E) None of the above

C) Mycoplasma

Which of the following pairs is mismatched? A) Corynebacterium gram-positive rod B) Mycobacterium acid-fast rod C) Mycoplasma gram-positive pleomorphic rod D) Bordetella gram-negative pleomorphic rod E) Haemophilus gram-negative rod

C) Mycoplasma gram-positive pleomorphic rod

Purplish spots on the skin are characteristic of an infection by A) C. neoformans. B) H. influenzae. C) N. meningitidis. D) S. pneumoniae. E) M. leprae.

C) N. meningitidis.

Microscopic examination of cerebrospinal fluid reveals amoebae. What is the organism? A) Haemophilus B) Listeria C) Naegleria D) Neisseria E) Streptococcus

C) Naegleria

Which of the following diseases is not correctly matched to a virulence factor? A) Diphtheria exotoxin B) Scarlet fever exotoxin C) Pneumococcal pneumonia exotoxin D) Haemophilus pneumonia endotoxin E) Whooping cough endotoxin

C) Pneumococcal pneumonia exotoxin

A patient has fever, difficulty breathing, chest pains, fluid in the alveoli, and a positive tuberculin skin test. Gram-positive cocci are isolated from the sputum. The patient most likely has A) Tuberculosis. B) Influenza. C) Pneumococcal pneumonia. D) Mycoplasmal pneumonia. E) Common cold.

C) Pneumococcal pneumonia.

A 17-year-old male has pus-filled cysts on his face and upper back. Microscopic examination reveals gram-positive rods. This infection is caused by A) Acanthamoeba. B) Herpes simplex virus. C) Propionibacterium acnes. D) Staphylococcus aureus. E) Streptococcus pyogenes.

C) Propionibacterium acnes.

You advise your pregnant friend to give her cat away because A) She could contract plague. B) She could give the cat tularemia. C) She could get toxoplasmosis. D) She could get listeriosis. E) You donʹt like cats and want to see your friend without one.

C) She could get toxoplasmosis.

Which of the following does not produce a gastrointestinal disease due to an exotoxin? A) Clostridium perfringens B) Vibrio cholerae C) Shigella dysenteriae D) Staphylococcus aureus E) Clostridium botulinum

C) Shigella dysenteriae

Thorough cooking of food will prevent all of the following except A) Trichinellosis. B) Beef tapeworm. C) Staphylococcal food poisoning. D) Salmonellosis. E) All of the above.

C) Staphylococcal food poisoning.

Which of the following leads to all the others? A) Toxemia B) Scalded skin syndrome C) Staphylococcal infection D) TSST-1 E) Sudden drop in blood pressure

C) Staphylococcal infection

Which of the following is treated with antibiotics? A) Botulism B) Tetanus C) Streptococcal pneumonia D) Polio E) All of the above

C) Streptococcal pneumonia

Which of the following is most susceptible to destruction by phagocytes? A) Chlamydophila psittaci B) Streptococcus pneumoniae C) Streptococcus pyogenes D) Influenzavirus E) All of the above

C) Streptococcus pyogenes

On June 30, a 47-year-old man was hospitalized with dizziness, blurred vision, slurred speech, difficulty swallowing, and nausea. Examination revealed facial paralysis. The patient had partially healed superficial knee wounds incurred while laying cement. He reported eating home-canned green beans and stew containing roast beef and potatoes 24 hours before onset of symptoms. The patient should be treated with A) Antibiotics. B) Antitoxin. C) Surgery. D) Vaccination.

C) Surgery.

A diagnosis of strep throat is confirmed by all of the following except A) Hemolytic reaction. B) Bacitracin inhibition. C) Symptoms. D) Serological tests. E) Gram stain.

C) Symptoms.

9) All of the following are true about rabies except A) It is caused by Rhabdovirus. B) Hydrophobia is an early symptom. C) The reservoir is mainly rodents. D) Diagnosis is based on immunofluorescent techniques. E) It is not fatal in bats.

C) The reservoir is mainly rodents.

Human-to-human transmission of plague is usually by A) Rat flea. B) Dog flea. C) The respiratory route. D) Wounds. E) None of the above.

C) The respiratory route.

Which of the following is not a cause of ringworm? A) Microsporum B) Trichophyton C) Tinea capitis D) Epidermophyton E) None of the above

C) Tinea capitis

The greatest single cause of blindness in the world is A) Neonatal gonorrheal ophthalmia. B) Keratoconjunctivitis. C) Trachoma. D) Inclusion conjunctivitis. E) Pinkeye.

C) Trachoma.

Which of the following organisms is likely to be transmitted via contaminated pork? A) Salmonella B) Staphylococcus C) Trichinella D) Entamoeba E) Shigella

C) Trichinella

Which one of the following is not transmitted by water? A) Salmonella B) Cyclospora C) Trichinella D) Cryptosporidium E) Hepatitis A virus

C) Trichinella

Used to treat epidemic herpetic keratitis. A) Penicillin B) Sulfonamide C) Trifluridine D) Fungicide E) None of the above

C) Trifluridine

Which of the following respiratory infections can be contracted by ingestion? A) Streptococcal pharyngitis B) Diphtheria C) Tuberculosis D) Mycoplasmal pneumonia E) Haemophilus pneumonia

C) Tuberculosis

Patients with leprosy usually die from A) Brain damage. B) Loss of nerve function. C) Tuberculosis. D) Influenza. E) Leprosy.

C) Tuberculosis.

Which of the following is a symptom of brucellosis? A) A local infection B) Relapsing fever C) Undulant fever D) Pneumonia E) Jaundice

C) Undulant fever

Clostridium difficile-associated diarrhea is usually preceded by A) Eating contaminated food. B) A blood transfusion. C) Use of broad-spectrum antibiotics. D) Improper food storage. E) Travel to an underdeveloped country.

C) Use of broad-spectrum antibiotics.

Most gastrointestinal infections are treated with A) Antitoxin. B) Penicillin. C) Water and electrolytes. D) Quinacrine. E) None of the above.

C) Water and electrolytes.

A man is suffering severe foot pain in the area of what looks like a large wart. He reports he has had the wart for some time, and the pain and swelling have developed slowly. A sample from the lesion shows that the pus contains large cells that stain a golden brown color. The man is likely suffering from a) sporotrichosis b) phaeohyphomycosis c) mycetoma d) chromblasomyosis e) necrotizing fasciitis

D

Impetigo can be caused by a) Staphylococcus epidermidis b) Streptococcus pyogenes c) Staphylococcus aureus d) both Staphylococcus aureus and Streptococcus pyogenes e) both Staphylococcus epidermidis and Streptococcus pyogenes

D

Shingles, or herpes zoster, is caused by the same virus that causes a) whitlows b) smallpox c) measles d) chickenpox e) German measles

D

Smallpox was the first human disease to be a) analyzed and studied on the genetic level b) identified as a viral disease c) treated with antiviral drugs d) globally eradicated e) re-created in an experimental animal

D

The common name for a furuncle is a) a sty b) acne c) a rash d) a boil e) a wart

D

The rash described as "teardrops on rose petals" is characteristic of a) warts b) smallpox c) anthrax d) chickenpox e) herpes

D

The resistance of Pseudomonas to a wide variety of antimicrobial drugs is due, in part, to its a) production of exoenzyme S. b) production of pyocyanin c) ability to utilize a wide range of carbon and nitrogen sources d) ability to pump drugs out of the cell e) ability to grow in almost any moist environment

D

All of the following are requirements for an outbreak of botulism except A) Killing bacteria that compete with Clostridium. B) An anaerobic environment. C) An incubation period. D) A nutrient medium with a pH below 4.5. E) None of the above.

D) A nutrient medium with a pH below 4.5.

Which of the following leads to all the others? A) Subcutaneous hemorrhaging B) Presence of antirickettsial antibodies C) Blockage of capillaries D) Bacterial growth in endothelial cells E) Breakage of capillaries

D) Bacterial growth in endothelial cells

Which of the following etiologic agents results in the formation of abscesses? A) Staphylococcus B) Mycoplasma C) Streptococcus D) Blastomyces E) None of the above

D) Blastomyces

10) The symptoms of tetanus are due to A) Deep puncture wounds. B) Hemolysins. C) Lack of oxygen. D) Clostridial neurotoxin. E) All of the above.

D) Clostridial neurotoxin.

Which of the following diseases is not correctly matched to its reservoir? A) Tuberculosis cattle B) Histoplasmosis soil C) Psittacosis parakeets D) Coccidioidomycosis air E) Pneumocystis humans

D) Coccidioidomycosis air

Which of the following is not transmitted by the respiratory route? A) Smallpox B) Chickenpox C) German measles D) Cold sore E) None of the above

D) Cold sore

5) Which of the following pairs is mismatched? A) Neisseria meningitidis cultured in a candle jar B) Haemophilus influenzae virulence due to capsule C) Mycobacterium leprae cultured in armadillos D) Cryptococcus neoformans acid-fast rod E) Naegleria fowleri causes amoebic encephalitis

D) Cryptococcus neoformans acid-fast rod

All of the following facts about Chagasʹ disease are true except A) Causative agent T. cruzi. B) Vector kissing bug. C) Reservoir rodents. D) Diagnosis serological tests for antibodies. E) Treatment Nifurtimox.

D) Diagnosis serological tests for antibodies.

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

D) Escherichia coli.

Used to treat candidiasis. A) Penicillin B) Sulfonamide C) Trifluridine D) Fungicide E) None of the above

D) Fungicide

Used to treat sporotrichosis. A) Penicillin B) Sulfonamide C) Trifluridine D) Fungicide E) None of the above

D) Fungicide

The most common cause of meningitis in children is A) Mycobacterium tuberculosis. B) Streptococcus pneumoniae. C) Cryptococcus neoformans. D) Haemophilus influenzae. E) Neisseria meningitidis.

D) Haemophilus influenzae.

In humans, beef tapeworm infestations are acquired by A) Ingesting the eggs of Taenia saginata. B) Ingesting segments of adult tapeworms. C) Ingesting contaminated water. D) Ingesting cysticerci in the intermediate host. E) Ingesting contaminated definitive hosts.

D) Ingesting cysticerci in the intermediate host.

All of the following are true about the lepromin test except A) It consists of human tissue extract. B) It detects the presence of anti-M. leprae antibodies. C) It is negative in the lepromatous form. D) It consists of M. leprae. E) None of the above.

D) It consists of M. leprae.

All of the following statements about congenital rubella syndrome are true except A) It is contracted in utero. B) It may be fatal. C) It may result in deafness, blindness, and mental retardation. D) It doesnʹt occur with subclinical infections. E) All of the above are true.

D) It doesnʹt occur with subclinical infections.

Which of the following is not true about toxoplasmosis? A) It is caused by a protozoan. B) The reservoir is cats. C) It is transmitted by the gastrointestinal route. D) It is a severe illness in adults. E) It can be congenital.

D) It is a severe illness in adults.

All of the following statements about otitis media are true except A) It is caused by Streptococcus pyogenes. B) It is a complication of tonsillitis. C) It is transmitted by swimming pool water. D) It is caused by rhinovirus. E) It is caused by Staphylococcus aureus

D) It is caused by rhinovirus.

All of the following statements about rheumatic fever are true except A) It is a complication of a Group A beta-hemolytic streptococcal infection. B) It is an inflammation of the heart. C) It is an inflammation of the joints. D) It is cured with penicillin. E) The incidence has declined in the last 10 years.

D) It is cured with penicillin.

All of the following statements about septicemia are true except A) Symptoms include fever and decreased blood pressure. B) Lymphangitis may occur. C) Symptoms are due to bacterial endotoxin. D) It usually is caused by gram-positive bacteria. E) It may be aggravated by antibiotics.

D) It usually is caused by gram-positive bacteria.

Most of the normal microbiota of the digestive system are found in the A) Mouth. B) Stomach. C) Small intestine. D) Large intestine. E) C and D.

D) Large intestine.

Which one of the following organisms does not belong with the others? A) Blastomyces B) Coccidioides C) Histoplasma D) Mycobacterium E) Pneumocystis

D) Mycobacterium

Which one of the following produces small ʺfried-eggʺ colonies on medium containing horse serum-yeast extract? A) Chlamydophila B) Legionella C) Mycobacterium D) Mycoplasma E) Streptococcus

D) Mycoplasma

Penicillin is used to treat all of the following except A) Streptococcal sore throat. B) Diphtheria. C) Pneumococcal pneumonia. D) Mycoplasmal pneumonia. E) Scarlet fever.

D) Mycoplasmal pneumonia.

Which of the following is not a causative agent of conjunctivitis? A) Chlamydia trachomatis B) Herpes simplex C) Adenovirus D) Neisseria gonorrhoeae E) Hemophilus aegyptii

D) Neisseria gonorrhoeae

A 1-year-old female was hospitalized with fever, lethargy, and rash. Gram -negative, oxidase-positive cocci were cultured from her cerebrospinal fluid. Her symptoms were caused by A) A prion. B) Clostridium tetani. C) Mycobacterium leprae. D) Neisseria meningitidis. E) Rabies.

D) Neisseria meningitidis.

The etiologic agent of fifth disease. A) Herpes simplex B) Herpes zoster C) HHV-6 D) Parvovirus E) Poxvirus

D) Parvovirus

Which of the following pairs is mismatched? A) Borrelia relapsing fever B) Yersinia plague C) Streptobacillus rat-bite fever D) Pasteurella cat-scratch disease E) Spirillum rat-bite fever

D) Pasteurella cat-scratch disease

Which of the following pairs is mismatched? A) Subacute bacterial endocarditis alpha-hemolytic streptococci B) Acute bacterial endocarditis Staphylococcus aureus C) Pericarditis Streptococcus pneumoniae D) Puerperal sepsis Staphylococcus aureus E) None of the above

D) Puerperal sepsis Staphylococcus aureus

The incidence of all of the following diseases is increased by unsanitary and crowded conditions except A) Plague. B) Epidemic typhus. C) Endemic murine typhus. D) Rocky Mountain spotted fever. E) Relapsing fever.

D) Rocky Mountain spotted fever.

The patient has vesicles and scabs over her forehead. Microscopic examination of skin scrapings shows gram-positive cocci in clusters. A) Candida B) Microsporum C) P. aeruginosa D) S. aureus E) Scabies

D) S. aureus

Which of these is not caused by herpesvirus? A) Chickenpox B) Shingles C) Keratoconjunctivitis D) Smallpox E) None of the above

D) Smallpox

Acute gastroenteritis that occurs after an incubation period of 4 to 24 hours is probably caused by A) Giardia B) Rotavirus C) Salmonella D) Staphylococcus aureus E) Trichinella

D) Staphylococcus aureus

Which of the following is sensitive to penicillin? A) Chlamydia B) Herpesvirus C) Candida D) Streptococcus E) Pseudomonas

D) Streptococcus

Which one of the following causes a disease characterized by a red rash? A) Blastomyces B) Coccidioides C) Mycoplasma D) Streptococcus E) None of the above

D) Streptococcus

With which of the following substrates can Streptococcus mutans make a capsule? A) Fructose B) Glucose C) Mannitol D) Sucrose E) All of the above

D) Sucrose

Scrapings from a patientʹs rash reveal cercariae. The disease is most likely A) Lyme disease. B) Rocky Mountain spotted fever. C) Relapsing fever. D) Swimmerʹs itch. E) Chagasʹ disease.

D) Swimmerʹs itch.

All of the following statements about salmonellosis are true except A) It is a bacterial infection. B) It requires a large infective dose. C) A healthy carrier state exists. D) The mortality rate is high. E) It is often associated with poultry products.

D) The mortality rate is high.