THE MOLECULAR BASIS OF INHERITANCE
DNA REPLICATION
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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not copied
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copied continuously
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copied backwards in pieces
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discarded
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Detailed explanation-1: -To get around this problem, this strand is synthesized in small pieces backward from the overall direction of replication. This strand is called the lagging strand. The short segments of newly assembled DNA from which the lagging strand is built are called Okazaki fragments.
Detailed explanation-2: -On the leading strand, DNA synthesis occurs continuously. On the lagging strand, DNA synthesis restarts many times as the helix unwinds, resulting in many short fragments called “Okazaki fragments.” DNA ligase joins the Okazaki fragments together into a single DNA molecule.
Detailed explanation-3: -The lagging strand is a single DNA strand that, during DNA replication, is replicated in the 5′ – 3′ direction (opposite direction to the replication fork). DNA is added to the lagging strand in discontinuous chunks called ‘okazaki fragments’.
Detailed explanation-4: -Leading and lagging strands One new strand, the leading strand, runs 5’ to 3’ towards the fork and is made continuously. The other, the lagging strand, runs 5’ to 3’ away from the fork and is made in small pieces called Okazaki fragments.
Detailed explanation-5: -Lagging strand is synthesised in fragments. Nucleotides cannot be added to the phosphate (5’) end because DNA polymerase can only add DNA nucleotides in a 5’ to 3’ direction. The lagging strand is therefore synthesised in fragments. The fragments are then sealed together by an enzyme called ligase.