AP BIOLOGY

Detailed explanation-1: -One of the key molecules in DNA replication is the enzyme DNA polymerase. DNA polymerases are responsible for synthesizing DNA: they add nucleotides one by one to the growing DNA chain, incorporating only those that are complementary to the template.

Detailed explanation-2: -As the new nucleotides line up opposite each parent strand by hydrogen bonding, enzymes called DNA polymerases join the nucleotides by way of phosphodiester bonds.

Detailed explanation-3: -These enzymes are essential to DNA replication and usually work in pairs to create two identical DNA strands from one original DNA molecule. During this process, DNA polymerase “reads” the existing DNA strands to create two new strands that match the existing ones.

Detailed explanation-4: -During initiation, so-called initiator proteins bind to the replication origin, a base-pair sequence of nucleotides known as oriC. This binding triggers events that unwind the DNA double helix into two single-stranded DNA molecules.

Detailed explanation-5: -The sliding-clamp proteins ( protein in E. coli and proliferating cell nuclear antigen [PCNA] in eukaryotes) bind adjacent to the clamp-loading proteins, forming a ring around the template DNA. The clamp proteins then load the DNA polymerase onto DNA at the primer-template junction.