Class 12th Biology 2016 Set3 Outside Delhi Board Paper Solution
Explain the mechanism of DNA replication.Highlight the role of enzymes in the process.
The replication begins in definite regions which are called the origin of replication , Replication occurs within a small opening of the DNA referred to as Y shaped replication fork (uncoiling of DNA is by some enzymes eg Helicase and topoisome rase), Polymerisation of the nucleotides are catalysed by DNA dependent DNA polymerase in 5' - 3' directions , Deoxyribonucleotides act as substrates and also provide energy for the process , The new strands formed on 3 '-5' template is continuous, New strands formed on 5-'3' template is discontinuous, The discontinuously formed fragments are joined by enzyme DNA ligase.
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