THE MOLECULAR BASIS OF INHERITANCE
DNA REPLICATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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catalyzes the synthesis of the RNA primer
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Breaks and rejoins the DNA double helix to relieve twisting forces caused by the opening of the helix
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stabilizes single-stranded DNA
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catalyzes the breaking of hydrogen bonds between base pairs to open the double helix by unwinding at the replication fork
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Detailed explanation-1: -An enzyme called helicase unwinds the DNA by breaking the hydrogen bonds between the nitrogenous base pairs.
Detailed explanation-2: -Helicase opens up the DNA at the replication fork. Single-strand binding proteins coat the DNA around the replication fork to prevent rewinding of the DNA. Topoisomerase works at the region ahead of the replication fork to prevent supercoiling. Primase synthesizes RNA primers complementary to the DNA strand.
Detailed explanation-3: -DNA helicases are molecular motors. Through conformational changes caused by ATP hydrolysis and binding, they move along the template double helix, break the hydrogen bonds between the two strands and separate the template chains, so that the genetic information can be accessed.
Detailed explanation-4: -Key enzyme involved in DNA replication, it is responsible for ‘unzipping’ the double helix structure by breaking the hydrogen bonds between bases on opposite strands of the DNA molecule.