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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DNA polymerase begins adding RNA nucleotides
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DNA polymerase begins adding DNA nucleotides
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DNA ligase joins the Okazaki fragments
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primase adds a primer made of RNA nucleotides.
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Detailed explanation-1: -The initiation of DNA replication occurs in two steps. First, a so-called initiator protein unwinds a short stretch of the DNA double helix. 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.
Detailed explanation-2: -It is critical that primers are synthesized by primase before DNA replication can occur. This is because the enzymes that synthesize DNA, which are called DNA polymerases, can only attach new DNA nucleotides to an existing strand of nucleotides. Therefore, primase serves to prime and lay a foundation for DNA synthesis.
Detailed explanation-3: -Finally, elongation–the addition of nucleotides to the new DNA strand–begins after the primer has been added.
Detailed explanation-4: -DNA primase is an enzyme involved in the replication of DNA and is a type of RNA polymerase. Primase catalyzes the synthesis of a short RNA (or DNA in some living organisms) segment called a primer complementary to a ssDNA (single-stranded DNA) template.