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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2 completely new DNA molecules
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2 DNA molecules that each contain a strand of the original
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1 new DNA molecule and 1 old
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1 new molecule of DNA
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Detailed explanation-1: -This process is known as semi-conservative replication because two copies of the original DNA molecule are produced, each copy conserving (replicating) the information from one half of the original DNA molecule. Each copy contains one original strand and one newly-synthesized strand.
Detailed explanation-2: -One of the most important concepts of DNA replication is that it is a semi-conservative process (Figure 7.2. 7). This means that every double helix in the new generation of an organism consists of one complete “old” strand and one complete “new” strand wrapped around each other.
Detailed explanation-3: -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-4: -During DNA replication, each of the two strands that make up the double helix serves as a template from which new strands are copied. The new strand will be complementary to the parental or “old” strand. Each new double strand consists of one parental strand and one new daughter strand.
Detailed explanation-5: -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.