THE MOLECULAR BASIS OF INHERITANCE
STRUCTURE OF NUCLEIC ACIDS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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leading strand
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lagging strand
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Detailed explanation-1: -All known DNA polymerases share two fundamental properties that carry critical implications for DNA replication (Figure 5.2). First, all polymerases synthesize DNA only in the 5′ to 3′ direction, adding a dNTP to the 3′ hydroxyl group of a growing chain.
Detailed explanation-2: -The dimeric structure of the DNA polymerase III holoenzyme couples leading and lagging strand DNA syntheses during replication. Leading strand synthesis (bottom strand) is continuous and processive, but lagging strand synthesis must reinitiate many times during replication of the chromosome.
Detailed explanation-3: -The leading strand is synthesized continuously while the lagging strand is synthesized discontinuously.
Detailed explanation-4: -On the upper lagging strand, synthesis is discontinuous, since new RNA primers must be added as opening of the replication fork continues to expose new template. This produces a series of disconnected Okazaki fragments.