What are leading strand and lagging strand?
The leading strand is the strand of nascent DNA which is synthesized in the same direction as the growing replication fork. The synthesis of leading strand is continuous. The lagging strand, on the other hand, is the strand of new DNA whose direction is opposite to the direction of the growing replication fork.
Is daughter strand leading or lagging?
The second daughter strand, called the lagging strand, is made discontinuously in small segments, called Okazaki fragments in honor of their discoverer.
What is leading and lagging strand synthesis?
The leading strand is synthesized in a continuous manner, whereas synthesis of the lagging strand requires a primase that makes RNA primers that are extended by the DNA polymerase to form Okazaki fragments — short DNA fragments that are processed to produce a continuous DNA strand.
What is the main reason for there being both a leading and a lagging strand during DNA replication?
Dna : Example Question #1 What is the main reason for there being both a leading and a lagging strand during DNA replication? Explanation: When the DNA helix is opened by DNA helicase, both strands are available to be read by DNA polymerase.
What is a daughter strand?
Daughter strand Refers to the newly synthesized strand of DNA that is copied via the addition of complementary nucleotides from one strand of pre-existing DNA during DNA replication.
Is the 5 or 3 strand the lagging strand?
Therefore, to form a continuous strand, the leading strand does not require ligase while the lagging strand requires ligase to ligate Okazaki fragments together. Furthermore, the leading strand opens in the 3′ to 5′ direction while the lagging strand opens in the 5′ to 3′ direction.
Why are lagging strands created?
Why must there be a lagging strand during DNA synthesis? Explanation: The lagging strand exists because DNA is antiparallel and replication always occurs in the 5′ to 3′ direction.
Who discovered RNA primers?
the Nobel Prize in Chemistry went to Roger Kornberg, PhD, for his work in understanding how DNA is converted into RNA, a process known as transcription.
What was Okazakis experiment?
Okazaki used a pulse chase type experiment to confirm discontinuous strand replication. He took actively replicating DNA, then added “hot” tritiated nucleotides for a short pulse of about 5 seconds. During the 5 seconds the radioactive nucleotides were incorporated into the growing DNA strands.
How are lagging strands formed?
Lagging strand synthesis begins when helicase opens up the parent molecule of DNA and creates the replication fork. Two molecules of helicase open the DNA in both directions, allowing DNA replication to occur both ways. This creates two leading strands and two lagging strands per replication fork.
Why are leading and lagging strands necessary?
How is the leading strand made?
One new strand, which runs 5′ to 3′ towards the replication fork, is the easy one. This strand is made continuously, because the DNA polymerase is moving in the same direction as the replication fork. This continuously synthesized strand is called the leading strand.