Question

Draw a labelled schematic sketch of replication fork of DNA. Explain the role of enzymes involved in DNA replication.

Answer 1

Helicase

DNA replication begins at places called origins, within the DNA molecule and the creation of replication forks. The process of strand separation is made possible because of the enzyme Helicase, which separates the two strands using the energy derived from ATP hydrolysis.

Primase

DNA primase is an enzyme involved in the replication of DNA and is a type of RNA polymerase. Primase catalyzes the synthesis of a short RNA segment called a primer complementary to a ssDNA template.

DNA polymerase

DNA polymerase is an enzyme that synthesizes DNA molecules from deoxyribonucleotides, the building blocks of DNA. These enzymes are essential for DNA replication and usually work in pairs to create two identical DNA strands from a single original DNA molecule.

Exonuclease

an enzyme which removes successive nucleotides from the end of a polynucleotide molecule.

DNA ligase

DNA ligase is a specific type of enzyme, a ligase, (EC 6.5.1.1) that facilitates the joining of DNA strands together by catalyzing the formation of a phosphodiester bond.