Class 12th Biology 2011 Set3 Delhi Board Paper Solution
Question 21
Why do you see two different types of replicating strands in the given DNA replication form? Explain. Name these strands.
Answer
We see two different types of replicating strands in the given DNA replication form because DNA polymerase can polymerise only in one direction that is 5´€™´†’3´€™. Therefore, replication occurs smoothly at 3´€™´†’ 5´€™end of DNA. While on the other (template with polarity 3´€™´†’5´€™), it is discontinuous. These two strands are known as leading and lagging strands respectively.
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