51. In which of the following, lipo-polysaccharide is a major constituent of outer membrane of the cellwall?
A. Gram-positive bacteria
B. Gram-negative bacteria
D. None of these
52. Which of the following structure(s) is /are external to cell wall?
D. All of these
53. Which of the following may be most likely to be missing from a gram-positive bacterium?
A. Penicillin-binding protein
D. Phospholipid bilayer membrane