Each question in this quiz is timed.
One of the signals required in the isotype switch of antibodys is:
A)Binding of CD40L on t cells with CD40 on b cells
B) Binding of ICAM-1 with LFA-1
C) Binding of B7 with CD28
D) Non of the above
Which of the following Abs increases with intrauterine infection?
Secretory portion of IgA is synthesized by :
A) epithelial cells
B) submucosal plasma cells
C) A & B
Which of the following stabilizes C3 convertase in the alternative pathway of complement activation:
C) Decay acceleration factor
D) all of the above
C3b receptor is found on the following cells except:
B) B cell
D) non of the above
Obligate fermenters are:
A) Obligate anaerobes
D) Aerotolerant anaerobes
Bacilli can form endospores in which of the following phases?
A) Stationary phase
B) Lag phase
C) Exponential phase
D) Decline phase
Which of the following is an acidophilic bacterium?
A) Vibrio cholera
Plasmids can be integrated into chromosomes forming:
Which of the following substances kill same or closely related species of bacteria?
C) A &B