AP BIOLOGY

Detailed explanation-1: -An RNA primer is a short segment of single-stranded RNA used as a binding site for DNA polymerase to initiate DNA replication. DNA polymerase is only able to add nucleotides to an existing nucleotide chain; it cannot “start from scratch, ” and therefore needs the RNA primer to start the process.

Detailed explanation-2: -A primer is a short nucleic acid sequence that provides a starting point for DNA synthesis. In living organisms, primers are short strands of RNA. A primer must be synthesized by an enzyme called primase, which is a type of RNA polymerase, before DNA replication can occur.

Detailed explanation-3: -Primase is the enzyme that synthesizes RNA primers. Primers are oligonucleotides that are complementarily bound to a DNA template and from which DNA polymerases elongate. Special proteins are responsible for loading primase at the origin of replication so that leading strand DNA synthesis can commence.

Detailed explanation-4: -Once the RNA primer is in place, DNA polymerase “extends” it, adding nucleotides one by one to make a new DNA strand that’s complementary to the template strand.