THE MOLECULAR BASIS OF INHERITANCE
DNA REPLICATION
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
relieve stress in DNA in front of the replication fork
|
|
|
unwind the double helix by breaking hydrogen bonds
|
|
|
add nucleotides to the new strand of DNA
|
|
|
add an RNA primer to the new strand of DNA
|
Detailed explanation-1: -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-2: -To unwind a long stretch of DNA, a helicase has to move unidirectionally along the DNA and couple translocation to local base pair separation. As the helicase moves along the DNA, it successively makes and breaks interactions with the DNA.
Detailed explanation-3: -DNA helicase is an enzyme that unwinds the DNA double helix by breaking the hydrogen bonds between the complementary bases.
Detailed explanation-4: -During initiation, so-called initiator proteins bind to the replication origin, a base-pair sequence of nucleotides known as oriC. This binding triggers events that unwind the DNA double helix into two single-stranded DNA molecules.
Detailed explanation-5: -DNA helicases catalyze the disruption of the hydrogen bonds that hold the two strands of double-stranded DNA together. This energy-requiring unwinding reaction results in the formation of the single-stranded DNA required as a template or reaction intermediate in DNA replication, repair and recombination.