Which cellular structure is important in classifying a bacterial species asGram positive or Gram negative?
A. flagella
B. cell wall
C. cell membrane
DNA sequence in chromosome
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Which of the following method is right about Gram stain?
A. Crystal violet stain – iodine fixation--- alcohol destain – safranine restain.
B. Crystal violet stain – alcohol destain --- safranine restain -- iodine fixation.
C. Iodine stain –Crystal violet fixation--- alcohol destain – safranine restain.
D. Safranine stain – iodine fixation--- alcohol destain –Crystal violet restain.
Which one is not the component of peptidoglycan of Gram positive bacterium
A. Tetapeptide side chain
B. pentapeptide cross bridge
C. bisaccharide backbone
D. lipopolysaccharide
About structure of peptidoglycan, which two molecules are linked alternately to make long bisaccharide chain?
A. NAM+NAG
B. NAM+DAP
C. DAP+NAG
DAP+LPS
Which one is the right order of the tetrapeptide side chain in peptidoglycan of Gram negative cell wall?
A. ala-glu-ala-DAP
B. DAP-ala-glu-ala
C. ala-glu-DAP-ala
D. ala-ala-glu-DAP