Complement System — Topic Test
6 questions · exam mode (answers revealed at the end). 18 min suggested.
A 19-year-old college student has sudden-onset fever, photophobia and neck stiffness. CSF Gram stain shows Gram-negative diplococci within neutrophils, and the isolate ferments both glucose and maltose. Which mechanism most explains why this organism can cause recurrent invasive disease despite an apparently intact humoral immune system?
AAntigenic variation of pili and Opa proteins with IgA1 protease production
BFormation of a biofilm on prosthetic heart valves
CIntracellular survival within macrophage phagolysosomes
DProduction of a single fixed capsular serotype that prevents opsonisation