43. The idea of selective toxicity was first proposed by
A.Antony van Leeuwenhoek
B.Paul Ehrlich
C.Louis Pasteur
D.Alexander Fleming

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44. Which of the following sequences has helped in identifying eukaryotes, eubacteria and archeabacterial cell types?
A.Signature sequence
B.Signal sequence
C.Shine-Dalgarno sequence
D.Amino acid sequence

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45. Archeal cells usually do not contain peptidoglycan, rather contain pseudo-peptidoglycan which is mainly composed of
A.N-acetylmuramic acid and L-amino acids
B.N-acetylmuramic acid and D-amino acids
C.N-acetyltalosaminuronic acid and D-amino acids
D.N-acetyltalosaminuronic acid and L-amino acids

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46. In the three domain system of classification, the traditional bacteria are placed in the
A.eukarya
B.archaea
C.eubacteria
D.none of these

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47. One of the reasons for the evolutionary success of the kingdom Monera is that its members are nutritionally diverse. Which of the following(s) is/are the way(s) of obtaining energy?
A.Photoautotrophy
B.Photoheterotrophy
C.Chemoheterotrophy
D.All of the above

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48. Carl Woese and his colleague are best known for establishing
A.the five kingdom system
B.the three domain system
C.the prokaryote-eukaryote system
D.the plant-animal system

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49. Which of the following is not found in the kingdom Monera?
A.Organelles
B.Organized cell structure
C.Ability to reproduce
D.Ability to use energy

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