CUET Preparation Today
Match column 1 with column 2:
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A-iv, B-iii, C-ii, D-i A-iii, B-iv, C-ii, D-i A-iv, B-ii, C-iii, D-i A-ii, B-i, C-iii, D-iv |
A-iv, B-iii, C-ii, D-i |
The correct answer is Option (1)- A-iv, B-iii, C-ii, D-i
A. In 1928, Frederick Griffith, in a series of experiments with Streptococcus pneumoniae (the bacterium responsible for pneumonia), witnessed a miraculous transformation in the bacteria.He concluded that the R strain bacteria had somehow been transformed by the heat-killed S strain bacteria. Some ‘transforming principle’, transferred from the heat-killed S strain, had enabled the R strain to synthesise a smooth polysaccharide coat and become virulent. This must be due to the transfer of the genetic material. B. The unequivocal proof that DNA is the genetic material came from the experiments of Alfred Hershey and Martha Chase (1952). They worked with viruses that infect bacteria called bacteriophages. C. Tha Matthew Meselson and Franklin Stahl experiment was to prove that DNA replicates semiconservative.It was shown first in Escherichia coli and subsequently in higher organisms, such as plants and human cell. D. In 1961, two French microbiologists,Francois Jacob and Jacque Monod at the Pasteur Institute, Paris proposed a mechanism,called operon hypothesis, for the regulation of gene action as a result of their studies on the metabolism in E.coli. |
