CELL DIVISION
CELL DIVISION AND CANCEROUS CELLS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Separating the two strands of the double helices
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Preventing double helices from over-winding and breaking by relieving tension
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Adding primers to template parent strands
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Synthesizing complementary daughter strands from template parent strands
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Detailed explanation-1: -Then, a protein known as helicase attaches to and breaks apart the hydrogen bonds between the bases on the DNA strands, thereby pulling apart the two strands. As the helicase moves along the DNA molecule, it continues breaking these hydrogen bonds and separating the two polynucleotide chains (Figure 1).
Detailed explanation-2: -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.
Detailed explanation-3: -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.
Detailed explanation-4: -Explanation: DNA helicase unwinds the double helix, separating the two strands so they may be replicated by DNA polymerase. Primase adds an RNA primer to help initiate DNA replication. DNA ligase is responsible for joining Okazaki fragments on the lagging strand during replication.
Detailed explanation-5: -To begin DNA replication, unwinding enzymes called DNA helicases cause the two parent DNA strands to unwind and separate from one another at the origin of replication to form two “Y-shaped” replication forks. These replication forks are the actual site of DNA copying.