Micr Bio Chp 19 Exam 4
What clinical manifestation do Staphylococcus aureus and Staphylococcus epidermidis share?
Which of the following has been historically classified as Gram-negative bacteria but its genetically more similar to low G + C Gram positive bacteria?
What is one virulence factor that differentiates Staphylococcus aureus from other species of staphylococci?
it can produce coagulase
Over 90% of Staphylococcus aureus isolates are penicillin-resistant. Why?
the produce B-lactamase
A woman comes to the emergency department with fever and vomiting. She soon develops a red rash all over her body, and her blood pressure begins to drop. What is one possible diagnosis?
toxic shock syndrome
Bacteria collected from a severely inflamed wound are sent to the lab for analysis. the results come back as follows: Gram-positive cocci in irregular clusters, kinase and coagulase positive, and able to grow in the presence of most antibiotics except vancomycin. the bacteria in the wound is most likely
methicillin-resistant Staphylococcus aureus (MRSA)
Streptococci are frequently classified by
Lancefield antigen designations
How do group A streptococci camouflage themselves from white blood cells?
they have hyaluronic acid capsules
Which of the following diseases is considered an autoimmune disease triggered by bacterial infection?
Which of the following statements about "flesh-eating" streptococci is FALSE?
It is considered a common complication of pyoderma
Streptococcus agalactiae is associated with which of the following diseases?
neonatal bacteremia, neonatal meningitis, and neonatal pheumonia
Which of the following statements regarding Streptococcus progenies is FALSE?
It produces protein A, which inhibits opsonization
What differentiates virulent strains of Streptococcus pneumonia from nonvirulent strains?
the presence of a polysaccharide capsule that protects it from digestion after endocytosis
Untreated streptococcal pharyngitis may progress to
scarlet fever or rheumatic fever
The Quellung reaction is used to diagnose
Otitis media may lead to dangerous meningitis in children due to infection with
Which of the following staphylococcal virulence factors produce the signs and symptoms of scalded skin syndrome?
During a stay in the hospital, an accident victim develops symptoms of bacteremia. A blood sample shows the presence of Gram-positive cocci in pairs. Lab tests determine that the bacteria are non hemolytic and bile salt tolerant. the bacteremia is likely due to
Which of the following streptococci is associated with dental caries?
Anthrax, which means "charcoal" in Greek, derives its name from
the black eschars it produces on human skin.
Which of the following statements about Bacillus anthraces is FALSE?
it is primarily a disease of humans
Which of the following bacteria produce one of the most deadly bacterial toxins known?
Which of the following bacteria can cause life-threating pseudomembranous colitis?
How does the toxin from Clostridium tetani produce its action?
The smaller polypeptide of its toxin can block the release of inhibitory neurotransmitters by inhibitory neurons in the CNS, causing simultaneous contraction of both muscles in an antagonistic pair.
Which of the following statements concerning tetanus is FALSE?
Its only source is from deep puncture wounds from rusty nails
Listeria virulence is directly related to its ability to
live within cells and thus avoid exposure to the immune system of its host
Which of the following bacteria divide by "snapping division" in which daughter cells remain attached in characteristic V-shapes?
Which of the following statements about diphtheria is FALSE?
its growth on Loeffler's medium is used for absolute diagnosis of the bacterium
Members of the genus Mycoplasma are pleomorphic and stain Gram-negative because they
lack cell walls
The pathogenicity of primary tuberculosis is due to the fact that the mycobacteria
prevent fusion of lysosomes with phagosomes
A sample of fluid from the lungs contains microbes that grow in filaments or clumps. the cells stain poorly in the Gram stain and are a pink-red when acid fast stained. the bacteria in the sample are
Under what conditions does infection with Mycobacterium leprae develop into tuberculoid leprosy?
when the immune system develops a vigorous cell mediated response
The pus from an abscess in a patients jaw contains microbes that form yellowish grainy masses and appear filamentous under the microscope. Neither anti fungal medication nor a normal course of antibiotics has been effective in treating the infection. the abscess is likely the result of infection with
What is the most common disease caused by Propionibacterium?
Mycetoma, which is a painless long lasting infection characterized by swelling, pus production, and draining sores, is caused by
the skin lesions characteristic of cutaneous infections with Bacillus anthraces are
The soil bacterium Nocardia asteroids can establish opportunistic infections of the
skin, lungs, and central nervous system
Enterococcus faecalis bacteria can be distinguished from other gram positive cocci because enterococci
can grow in the presence of bile salts
Infections with Streptococcus progenies may progress to _____, characterized by a skin rash that peels after about a week and a bright red swollen tongue.
Increased sebum secretion can fuel the overgrowth of the opportunistic pathogen ______ in its normal habitat, leading to disease.
Streptococcus pneumoniae is a leading cause of
Mycoplasma pneumoiae causes respiratory disease by
attaching to, inhibiting, and ultimately killing the ciliated epithelial cells of the trachea.
Which of the following is a key diagnostic indicator of infection with Mycobacterium leprae?
loss of the sense of touch
Which of the following is NOT a feature of the pathogenesis of Clostridium perfringens?
inhibiting sensory neuron function
Which of the following bacteria can cause pharyngitis?
A summer cold that lasts for weeks and is characterized by sore throat, mild fever, dry cough, and malaise may be (pneumococcal/walking) pneumonia.
the presence of mycelia acid in the cell walls of the opportunistic pathogen (Actinomyce/ Nocardia) results in it Gram staining poorly.
In its role in the development of acne, (propionibacterium/ staphylococcus/ actinomyces) typically grows in sebaceous glands of the skin.
(MRSA/ MDR-TB/ VRSA) is resistant to numerous antimicrobial agents; therefore, vancomycin is usually used for these infections.
In countries where tuberculosis is common, people are vaccinated with (BCG/DOTS/ MDR-TB)which contains attenuated Mycobacterium bovis bacteria.
Infection with Corynebacterium diphtheriae leads to the formation of (pseudomembranes/ tubercles) which can severely impair respiratory function.
Successful treatment of diphtheria requires the administration of (antibiotics/antitoxin/ immunoglobulin).
Common sources of Listeria are undercooked meats and vegetables and unpasteurized (eggs/ milk/ juices).
the neurotoxins of Clostridium botulinum produce (flaccid/ tetanic) paralysis by preventing muscle contraction.
Bacterial food poisoning resulting from Clostridium (botulinum/ difficele/ perfringens) contamination is characterized by watery diarrhea accompanied by intestinal cramping but not fever, and it resolves in about a day.
(Enterococcus/ Staphylococcus) grow at temperatures up to 45C, at pH levels as high as 9.6, and in 6.5% NaCl, but they lack structural and chemical elements that make them virulent in the intestinal tract.
The aerobic endospore former (Clostridium perfringens/ Clostridium difficle/ Bacillus anthracis) is a strict pathogen of humans and animals.
The body limits the migration of Streptococcus (agalactiae/ pneumoniae/ progenies) by binding it to the active sties of secretory IgA, which the bacteria overcome by secreting secretory IgA protease.
When streptococcal infections involve the skin and surrounding lymph nodes, triggering pain and inflammation, the condition is known as (erysipelas/ folliculitis/ pyoderma).
The ability to produce (hyalauronidase/ lipase/ proteases) enables Staphylococcus aureus to penetrate and spread through tissues.