Which is the infective and pathogenic stage of Trichomonas vaginalis?()
A. Trophozoite
B. Cyst and trophozoite
C. Mature cyst
D. Promastigote
E. Amostigote
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Which is the infective stage of malaria parasite when transmitted by mosquitoes?()
A. Trophozoite
B. Schizont
C. Sporozoite
D. Gametocyte
E. Ring form
The infective site of Paragonimus westermani adult is()
A. small intestine of the final host
B. colon of the final host
C. liver of the final host
D. lung of the final host
E. brain of the final host
Virus have characters which differ from Bacteria :()
A. sensitive to antibiotics
B. can grow in culture medium
C. pass through filter
D. have cell structure
E. Have two kinds of neucleic acid DNA and RNA
Which of following can cause the great variation of influenza virus and wide epidemic:()
A. gene reassortment
B. gene recombination
C. transduction
D. transformation
E. conjunction