THE MOLECULAR BASIS OF INHERITANCE
DNA REPLICATION
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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3’
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5’
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1’
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4’
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Detailed explanation-1: -During elongation, an enzyme called DNA polymerase adds DNA nucleotides to the 3′ end of the template. Because DNA polymerase can only add new nucleotides at the end of a backbone, a primer sequence, which provides this starting point, is added with complementary RNA nucleotides.
Detailed explanation-2: -DNA is always synthesized in the 5’-to-3’ direction, meaning that nucleotides are added only to the 3’ end of the growing strand. As shown in Figure 2, the 5’-phosphate group of the new nucleotide binds to the 3’-OH group of the last nucleotide of the growing strand.
Detailed explanation-3: -A DNA strand with the fifth carbon within the sugar ring at its terminus is said to have a five prime end. On the 3′ carbon of its terminal sugar, the 3′ end has a free hydroxyl group. The three prime ends of a molecule is the end that ends in a 3′ phosphate group.
Detailed explanation-4: -The addition of a deoxyribonucleotide to the 3′ end of a polynucleotide chain (the primer strand) is the fundamental reaction by which DNA is synthesized.
Detailed explanation-5: -DNA replication goes in the 5’ to 3’ direction because DNA polymerase acts on the 3’-OH of the existing strand for adding free nucleotides.