Biology 2261 Spring 1999 Second Examination Name ANNOUNCEMENT: On March 25 and March 30, class will meet in the Nursing Building, room 108. Be sure to put your name and your examination number on the mark-sense sheet. Put your name on the exam booklet. Both the exam booklet and the mark-sense sheet must be turned in at the end of the period. You may write in the exam booklet, but only the mark-sense sheet will be graded. No other paper, scratch paper, etc., may be used. Students must turn in the exam before leaving the room for any reason. A student may not continue working on the exam after having left the room. Multiple Choice. 50 questions, 2 pt each. 1. Which of the following indicates a possible case of tuberculosis? (a) (b) The presence of gram-negative cocci in the lung secretions of the patient. The presence of gram-negative rods with bipolar staining in the lung secretions of the patient. The presence of acid-fast rods in the lung secretions of the patient. A positive Weil-Felix test. A skin rash on the palms of the hands and soles of the feet. (c) (d) (e) 2. A patient is observed to have a severe upper respiratory tract with a loose, membranous tissue covering the back of the throat. Which of the following tests is indicated? (a) (b) (c) a Weil-Felix test acid-fast stain of the material from a throat swab a methylene blue simple stain to test for bacteria having metachromatic granules and coryneform arrangement a biochemical test to distinguish Salmonella from other Enterobacteriaceae staining the material from a throat swab with fluorescent antisera to detect a spirochete (d) (e) 3. The erythrogenic toxin produced by some strains of Streptococcus pyogenes is responsible for (a) the formation of heart lesions. Page 1 (b) (c) (d) (e) the skin rash of scarlet fever. the kidney damage that complicates streptococcal infections. ulceration in the gastrointestinal tract. blockage of nerve impulses at motor neuron end plates. Page 2 4. Hemophilus influenzae is recognized as an important cause of (a) (b) (c) (d) (e) meningitis in young children. cervical tumors. renal failure in patients with suppressed immune systems. skin ulcers in patients from tropical regions. chancroid. 5. A principal criterion for the diagnosis of meningitis due to Neisseria meningitidis is (a) (b) (c) (d) (e) observation of acid-fast rods in the spinal fluid. gram-negative cocci, arranged in pairs, in the spinal fluid. gram-negative rods in the spinal fluid. observations of mycoplasmas in the spinal fluid. gram-positive rods in the spinal fluid. 6. Both staphylococcal food poisoning and salmonellosis can be acquired by eating contaminated food. After eating contaminated food, the time required for the onset of staphylococcal food poisoning is shorter than that for salmonellosis because (a) Staphylococcus aureus grows more rapidly than Salmonella enteritidis serotypes. cells of Salmonella must reach the bloodstream before symptoms of gastrointestinal irritation are experienced. foods that contain Salmonella are usually eaten raw. Staphylococcus aureus grows only under conditions of high salt concentration. staphylococcal food poisoning is due to the presence of an exotoxin that forms in the food before it is eaten, but salmonellosis requires the colonization and growth of the bacteria in the intestine. (b) (c) (d) (e) 7. The botulism toxin causes flaccid paralysis by (a) (b) (c) (d) (e) causing swelling in the meninges. inhibiting the action of cholinesterase in the synapses of central nervous system neurons inhibiting protein synthesis in neurons. blocking synaptic transmission at the motor neuron end plates. causing the formation of gummae in the brain and spinal cord. 8. All of the following are related to typhoid fever EXCEPT (a) (b) (c) the causative agent is a member of the family Enterobacteriaceae. human carriers who show no symptoms may transmit the disease. ulcers may form in the intestine. Page 3 (d) (e) the organism is commonly found in almost all soil samples. a rose-colored rash often develops on the body. Page 4 9. Which of the following is a characteristic symptom of cholera? (a) (b) (c) (d) (e) relapsing fever “rice-water” stools with the extensive loss of fluid extreme jaundice blood in respiratory tract secretions rose-colored spots 10. The staphylococcal enterotoxin (a) (b) (c) (d) (e) is composed solely of Lipid A. is among the most heat-resistant of exotoxins. can be destroyed by placing food in a refrigerator. produces a condition of rigid paralysis. is more lethal than the botulism toxin. 11. Which of the following describes the organism responsible for bubonic plague? (a) (b) (c) (d) (e) a strictly aerobic, spore-forming rod a spirochete a gram-negative rod with bipolar staining a gram-positive rod with metachromatic granules a strictly anaerobic, spore-forming rod 12. The principal mode of transmission for Rocky Mountain Spotted Fever is (a) (b) (c) (d) (e) blood transfusion sexual contact bite of an infected tick inhalation of bacteria that cause the disease ingestion of food contaminated with bacterial spores 13. Epidemic typhus is likely to occur where sanitation is lacking and where hygiene is poor because (a) (b) (c) (d) (e) human lice flourish under these conditions. the typhus bacteria are usually transmitted by drinking contaminated water. unsanitary living conditions attract the ticks that transmit the disease. large numbers of live typhus bacteria are shed in the feces of infected persons. the typhus bacteria grow in urine-contaminated soil. 14. Endemic typhus may be expected to occur in regions where there are (a) (b) (c) large herds of cattle. large populations of deer ticks. large populations of rodents and fleas. Page 5 (d) (e) poultry processing plants. problems with the proper canning of food. 15. Wound infections of Clostridium perfringens are often accompanied by (a) (b) (c) (d) (e) large, open sores on the body. intestinal ulceration. a red-colored skin rash. gas gangrene. fluid buildup in the lung tissue. 16. The rigid paralysis and muscle spasms associated with tetanus are due to (a) (b) the invasion of muscle tissue by the tetanus bacteria. a neurotoxin that interferes with cholinesterase activity at the synapses of neurons. a neurotoxin that inhibits synaptic transmission at motor neuron end plates. an exotoxin that kills muscle cells by inhibiting protein synthesis in the cells. an erythrogenic toxin that causes hemorrhaging in the capillary beds that surround muscle tissue. (c) (d) (e) 17. Because the bacteria can enter the uterus and infect the fetus, these infections are associated with miscarriages or birth defects. (a) (b) (c) Listeria monocytogenes infections. Bordetella pertussis infections. Hemophilus ducreyi infections. 18. Erythema chronicum migrans (ECM) is the distinctive, ring-like skin lesion associated with (a) (b) (c) typhoid fever. Lyme disease. primary syphilis. 19. Infection due to Hemophilus ducreyi may be identified by the isolation of (a) (b) (c) (d) (e) gram-positive cocci from skin lesions. gram-negative cocci from the spinal fluid. gram-negative rods from the soft chancres. gram-positive rods from the feces. spirochetes from the vaginal secretions. 20. Escherichia coli (a) inhabits the large intestine and feces of most individuals. (d) (e) (d) (e) Page 6 Borrelia burgdorferi infections. Bacillus anthracis infections. tertiary syphilis. anthrax. (b) (c) (d) (e) is the major cause of primary atypical pneumonia. consists of acid-fast, funguslike rods. grows well and survives in soil and aquatic environments. cannot grow at human body temperature. 21. The hard chancre is a painless, purple-colored skin ulcer associated with (a) (b) (c) toxic shock syndrome. lyme disease. chlamydial urethritis. 22. Staphylococcus aureus has been linked to all of the following conditions EXCEPT (a) (b) (c) impetigo. toxic shock syndrome. Rocky Mountain Spotted Fever. 23. When the bacterium responsible for tuberculosis spreads from the lungs into other organs and tissues of the body, the resulting condition is known as (a) (b) (c) primary atypical tuberculosis. secondary tuberculosis. aseptic tuberculosis. 24. Which of the following is most often associated with bacterial dysentery? (a) (b) (c) (d) (e) Vibrio cholerae Species of the genus Shigella Salmonella enteriditis Species of the genus Clostridium Borrelia burgdorferi 25. Infantile diarrhea and traveller’s diarrhea are commonly caused by (a) (b) (c) Escherichia coli Clostridium botulinum Bacillus anthracis 26. This spirochete is often transmitted to humans by contact with soil contaminated with animal urine. It affects several organs, including the kidneys, liver, meninges, and gastrointestinal tract. It is (a) (b) (c) Borrelia burgdorferi Camphylobacter jejuni Listeria monocytogenes (d) (e) (d) (e) (d) (e) (d) (e) (d) Page 7 secondary syphilis. primary syphilis. the scalded skin syndrome. boils and pimples. miliary tuberculosis. rickettsial tuberculosis. Treponema pallidum Listeria monocytogenes Treponema pallidum (e) Leptospira interrogans Page 8 27. Which of the following is a characteristic of infections by Yersinia pestis? (a) (b) (c) Open, crusted sores at the site of the skin infections. Development of a painful soft chancre on the external genitalia. Infection and swelling of the lymph nodes accompanied by a purple or blackish discoloration of the skin. Intestinal ulceration. A reddish rash that begins in the palms of the hands and soles of the feet, then spreads to other areas of the body. (d) (e) 28. Which of the following tests is useful in the diagnosis of infections by species of the genus Rickettsia? (a) (b) (c) (d) (e) An acid-fast stain A Gram stain A Weil-Felix test Injecting Rickettsia antigens underneath the skin on the arm of the patient The hemolytic reaction of the Rickettsia species on blood agar 29. Which of the following organisms is responsible for epidemic typhus? (a) (b) (c) Salmonella typhi Rickettsia typhi Rickettsia prowazekii 30. The formation of lesions called gummae is associated with (a) (b) (c) chancroid Lyme disease tertiary syphilis 31. A small, gram-negative, obligately intracellular parasitic bacterium that is similar to Rickettsia and is associated with urinary tract infections, pelvic inflammatory disease, and eye infections is (a) (b) (c) Neisseria gonorrhoeae Hemophilus ducreyi Vibrio cholerae 32. A patient exhibits swollen, whitish skin lesions on the hands, feet and face. She also exhibits a loss of skin sensation due to nerve damage. Microscopic examination of a skin biopsy from an affected region revealed numerous acidfast, rod-shaped bacteria. However, the bacteria could not be grown in the laboratory on microbiological media. Which of the following conditions does she most likely suffer from? (d) (e) Rickettsia rickettsii Clostridium tetani (d) (e) (e) Page 9 tuberculosis secondary syphilis (d) Chlamydia trachomatis Treponema pallidum (a) (b) (c) anthrax erysipelas leprosy (d) (e) leptospirosis impetigo *********************************************************************** The following choices are used for questions 33 - 37. (a) (b) (c) (d) (e) Cells of this species are gram-positive cocci. Cells of this species are gram-negative cocci. Cells of this species are gram-positive rods. Cells of this species are gram-negative rods. Cells of this species are either spirochetes, spirilla, or vibrios. 33. Camphylobacter jejuni 34. Corynebacterium diphtheriae 35. Bordetella pertussis 36. Borrelia burgdorferi 37. Helicobacter pylori ******************************************************************** The following choices are used for questions 38 - 41. (a) (b) Streptococcus agalactiae Streptococcus fecalis (c) (d) Streptococcus pyogenes Streptococcus pneumoniae 38. This species is not included in the Lancefield classification system. 39. This species is an enterococcus. 40. This species belongs to Lancefield group A. 41. This species belongs to Lancefield group D. ********************************************************************* The following choices are used for questions 42 - 44. (a) (b) (c) alpha hemolysis beta hemolysis gamma reaction 42. Bacterial species that exhibit this property produce a green zone of partial hemolysis around their colonies on blood agar. Page 10 43. Group A streptococci typically exhibit this property on blood agar. 44. Streptococcus pneumoniae typically exhibits this property on blood agar. ********************************************************************* Page 11 The following choices are used for questions 45 - 46. (a) (b) (c) necrotizing fasciitis glomerulonephritis rheumatic fever (d) erysipelas (e) puerperal sepsis 45. This is a complication in which the immune response to a Streptococcus pyogenes infection causes damage to the cardiovascular system, especially the heart valves. 46. This is a complication in which muscle tissue is destroyed by hydrolytic enzymes produced by some strains of Streptococcus pyogenes. ********************************************************************** The following choices are used for questions 47 - 50. (a) (b) (c) (d) (e) Mycobacterium tuberculosis Streptococcus pneumoniae Neisseria meningitidis Legionella pneumophila Mycoplasma pneumoniae 47. Commonly found in aquatic habitats, this organism can contaminate moist aerated surfaces such as building ventilation systems. 48. In the lungs, the acid-fast rod-shaped cells of this species become surrounded by walls of connective tissue. 49. This organism, consisting of encapsulated gram-positive cocci arranged in pairs, is a frequent cause of secondary bacterial pneumonia. 50. This organism is frequently responsible for primary atypical pneumonia. *********************************************************************** Page 12