AP BIOLOGY

Detailed explanation-1: -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-2: -During DNA replication, DNA helicases unwind DNA at positions called origins where synthesis will be initiated. DNA helicase continues to unwind the DNA forming a structure called the replication fork, which is named for the forked appearance of the two strands of DNA as they are unzipped apart.

Detailed explanation-3: -DNA is double stranded in nature, and in order to be replicated, this structure has to be unzipped. The site of initial unwinding is referred to as the origin of replication. After that, other enzymes add new pieces of DNA to the unzipped strands in order to synthesize two new DNA molecules.

Detailed explanation-4: -The first step in DNA replication is the unzipping of DNA by the enzyme helicase. This opens up the DNA nucleotides so that they can be read and a complementary strand can be formed.