This type of replication is called discontinuous as the Okazaki fragments will need to be joined up later. Lagging strand: … Chunks of DNA, called Okazaki fragments, are then added to the lagging strand also in the 5′ to 3′ direction. 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. The synthesis of leading strand is continuous. The leading strand is the strand of nascent DNA which is synthesized in the same direction as the growing replication fork. A lagging strand requires a slight delay before undergoing replication, and it must undergo replication discontinuously in small fragments. Which is the lagging strand of DNA?Ī lagging strand is one of two strands of DNA found at the replication fork, or junction, in the double helix the other strand is called the leading strand. Okazaki fragments are formed on the lagging strand, as DNA polymerase synthesizes a section and then must wait for helicase to open up more of the DNA helix upstream. Okazaki fragments are short sequences of DNA nucleotides (approximately 150 to 200 base pairs long in eukaryotes) which are synthesized discontinuously and later linked together by the enzyme DNA ligase to create the lagging strand during DNA replication. This tricky strand, which is made in fragments, is called the lagging strand. This strand is made in fragments because, as the fork moves forward, the DNA polymerase (which is moving away from the fork) must come off and reattach on the newly exposed DNA. What is lagging strand in DNA replication? 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. Why are there lagging strands in DNA replication? The leading strand is synthesized continuously, whereas the lagging strand is synthesized in short pieces termed Okazaki fragments. At a replication fork, both strands are synthesized in a 5′ → 3′ direction. What direction are Okazaki fragments synthesized? Okazaki fragments are short sequences synthesized in the lagging strand because DNA polymerase can synthesize only from 5′ to 3′, and the DNA strands are antiparallel. Which of the following statements best describes Okazaki fragments? They are formed in the lagging strand. Which best describes Okazaki fragments in DNA replication? The primer for each new Okazaki fragment is synthesized in the 5′ to 3′ direction by primase (a DNA-dependent RNA polymerase), which is also component of the primosome along with helicase and other DNA binding proteins (Fig.
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