AP BIOLOGY

Detailed explanation-1: -The primer acts as the starting point for DNA synthesis. DNA polymerase? binds to the leading strand and then ‘walks’ along it, adding new complementary? nucleotide? bases (A, C, G and T) to the strand of DNA in the 5’ to 3’ direction. This sort of replication is called continuous.

Detailed explanation-2: -There are four basic components required to initiate and propagate DNA synthesis. They are: substrates, template, primer and enzymes.

Detailed explanation-3: -Therefore, DNA polymerases require a free 3′-OH group to which it can add free nucleotides by forming a phosphodiester bond between the 3′-OH end and the 5′ phosphate of the next nucleotide. This means that it cannot add nucleotides if a free 3′-OH group is not available.

Detailed explanation-4: -Complete answer: Joining of nucleotides in free bases or exposed bases of DNA takes place at the time of replication and transcription by base-pairing rule. The base-pairing rule is the pairing formed in DNA between the purine and pyrimidine.

Detailed explanation-5: -Although each nucleotide in DNA contains identical sugar and phosphate groups, there are four different bases and thus four different nucleotides that can be incorporated into DNA.