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Using the help of the semi conservative replication of DNA, What is the role of a single strand of DNA ?

User Lexy
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Answer:

In the semi-conservative method of DNA replication, each of the strands of the double helix acts as a template for replication.

Step-by-step explanation:

Semi-conservative DNA Replication:

  • Semi-conservative DNA replication produces two daughter helices from the original parent helix. One strand of the daughter helix is form the original template while the other is newly synthesized.
  • This means that one strand will have the base sequence identical to the parent, while the other will be complementary to the template.
  • This model was experimentally confirmed by an experiment conducted in 1958 by Meselson and Stahl. They used radioactive isotope of nitrogen i.e. N-14 or N-15. DNA molecules made with N-15 were allowed to replicate in the presence of N-14.
  • After first replication, DNA molecules contained both N-15 and N-14 isotopes, disproving the conservative model that stated that the new helices are completely identical to the template.
  • The second replication yielded only N-14 which disproved the dispersive model that the new helices are a combination of both the template and new strands.
User Besbes Riadh
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