Important methods for classifying and separating streptococci are
Agglutination using antisera against the cell wall group-specific substance
Biochemical testing
C. Hemolytic properties (α-, β-, nonhemolytic)
D. Capsular swelling (quellung) reaction
E. All of the above
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All of the following statements regarding the hyaluronic acid capsule of S. pyogenes are correct except
A. It is responsible for the mucoid appearance of the colonies in vitro
B. It is antiphagocytic
C. It binds to CD44 on human epithelial cells
D. It is an important virulence factor
E. A vaccine against the capsule is currently available
All of the following are virulence factors associated with N. gonorrhoeae except
A. Pili
B. Por
C. Lipooligosaccharide
D. Opa proteins
E. A thick polysaccharide capsule
Which one of the following microorganisms is closely associated with dental caries?
A. albicans
B. Streptococcus mutans
C. melaninogenica
D. Neisseria subflava
E. epidermidis
Reversion ofNeisseria gonorrhoeae from a fimbriated (fim 1) to a non-fimbriated (fim 2) state would result in which one of the following phenomena?
A. Inability of gonorrhoeae to colonize the mucosal epithelium
B. Reversion to a Gram-positive stain
C. Death of the organism
D. Loss of serologic specificity
E. A negative capsule strain
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