MICRO: Ch. 21 Mycoplasmas, Rickettsias, Chlamydias, Spirochetes, and Vibrios

Which of the following is true of spirochetes?

Borddetella Are: treponema, borrelia, leptospira, Thin, tightly coiled, helicaly shaped *Gram- pregnant women ability to penetrate

Epidemic typhus can recur many years after an initial episode, and the recurrent disease is called

Brill-Zinsser disease

Which of the following pathogens causes the most commonly reported sexually transmitted disease in the United States?

Chlamydia trachomatis

All of the following are true of both H. pylori and C. jejuni EXCEPT:

Gram negative *curved rods *lives in the stomach produces urease that buffers stomach acidity *Mouth is port of entry *Both have cuticles *motile

Which of the following statements regarding trachoma is incorrect?

It is most often a disease of adults who suffer from sexually transmitted chlamydia *True: bacteria infect conjunctiva & cause scarring, blindness

What characteristics of Borrelia burgdoferi makes it an unusual bacterium?

It utilizes manganese instead of iron in its proteins and enzymes.

Nongonococcal urethritis (NGU) is caused by

Mycoplasma genitalium

Which of the following microorganisms have been referred to as energy parasites?

Mycoplasmas

Scrub typhus is caused by

Orenta tsutsugamushi

Chlamydia trachomatis infects all of the following areas in humans EXCEPT:

The central nervous system True: trachea, (urinary tract) ( genital tract ) anus, rectum, bronchi, eye (conjunctiva ), lung

What characteristic does Vibrio share with Salmonella?

They have O polysaccharide antigens

Which of the following is NOT a characteristic of rickettsias?

True: Pleomorphic 2. Obligate intracellular bacteria 3. Gram negative rods (gram stain not useful) 4. Both DNA & RNA 5. Very small, divide by binary fusion 6. Parasite They can synthesize small amounts of peptidoglycan

Sexually transmitted chlamydia is similar to infection with Yersinia pestis in that they both produce

buboes Swelling in the lymph nodes, buboes in groin area

All of the following are spirochetes EXCEPT:

by infected fomites TRUE: sexually transmitted, rarely by blood transfusion, from mother, transplanted organs.

The most specific method for diagnosing chlamydia is by

demonstrating the presence of the pathogen in cell culture by means of fluorescent antibodies.

Rickettsia prowazekii is transmitted by

human body lice Pediculis humanus

Rocky mountain spotted fever (RMSF) is cuased by Rickettsia rickettsia, a pathogen that

infects the lining of blood vessels and leads to leaking of plasma into tissue.

Diagnosis of Treponema pallidum is best made by

inoculating laboratory animals to demonstrate the symptoms of disease. *specified antibiotic test MHA-TP TEST*

All of the following statements are true of Ehrlichia EXCEPT:

it usually causes a spotted rash similar to RMSF True: *transmitted by ticks *grow and reproduce with no host cell phagosomes (parasite) *3 stages *causes human monocyte erlichiosis & anaplasmosis

The most important virulence factor of Vibrio cholera is

its ability to produce a potent exotoxin; causes diarrhea

Leptospira interrogans gets its name from

the fact that one end of the spirochete is curved like a question mark

Why are mycoplasmas not considered viruses?

they contain both RNA and DNA