BIOLOGY
NUCLEIC ACIDS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Half of each new DNA is the old DNA
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The old strand of DNA was digested, so none
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The new DNA is entirely made up of the old DNA
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About every sixth base comes from the old DNA
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Detailed explanation-1: -The result of DNA replication is two DNA molecules consisting of one new and one old chain of nucleotides. This is why DNA replication is described as semi-conservative, half of the chain is part of the original DNA molecule, half is brand new.
Detailed explanation-2: -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-3: -Each new double strand consists of one parental strand and one new daughter strand. This is known as semiconservative replication. When two DNA copies are formed, they have an identical sequence of nucleotide bases and are divided equally into two daughter cells.
Detailed explanation-4: -These results were consistent with the semiconservative model of replication and the reality that, when DNA replicated, each new double helix was built with one old strand and one new strand.