The enzyme which catalyzes the unwinding of DNA helix during replication is:

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Q: 6 (SSC/0)
The enzyme which catalyzes the unwinding of DNA helix during replication is:

question_subject: 

Science

question_exam: 

SSC

stats: 

0,3,9,3,3,3,3

keywords: 

{'dna helix': [1, 0, 0, 0], 'dnapolymerase': [1, 0, 0, 0], 'enzyme': [8, 0, 2, 0], 'topoisomerase': [1, 0, 0, 0], 'helicase': [2, 0, 0, 0], 'replication': [2, 0, 0, 1], 'primase': [1, 0, 0, 0]}

The correct answer is option 3, Helicase. Helicase is the enzyme that catalyzes the unwinding of the DNA helix during replication. During DNA replication, the double-stranded DNA needs to be separated so that each strand can be used as a template for the synthesis of a new complementary strand. Helicase functions by breaking the hydrogen bonds between the base pairs and separates the two DNA strands, creating a replication fork. It does this by using energy from ATP hydrolysis. Once the DNA strands are separated, other enzymes like DNA polymerase can come in and add new nucleotides to form new strands. Primase (option 1) is responsible for synthesizing RNA primers that initiate DNA replication. Topoisomerase (option 2) helps relieve the strain caused by the unwinding of the DNA helix. DNA polymerase (option 4) is responsible for synthesizing new DNA strands by adding nucleotides to the growing chain.