Mastering DNA Replication Enzymes and Their Functions

Professor Dave explains DNA replication, detailing the structure of DNA, the role of enzymes like helicase, primase, and polymerase, and the processes involved in replicating leading and lagging strands. He highlights the accuracy of DNA polymerase and the mechanisms for error correction, ensuring genetic material is accurately copied during cell division.

What is the primary function of DNA replication in cells?

• To repair damaged DNA

• To produce energy for the cell

• To ensure each new cell has a complete set of genetic material

• To create new proteins

Which enzyme is responsible for unwinding the DNA double helix?

• Topoisomerase

• Ligase

• Primase

• Helicase

What role does primase play in DNA replication?

• It unwinds the DNA strands

• It joins Okazaki fragments

• It synthesizes RNA primers

• It proofreads the DNA sequence

How does DNA polymerase III function differently on the leading and lagging strands?

• It only works on the lagging strand

• It works continuously on both strands

• It synthesizes DNA in fragments on the leading strand

• It works continuously on the leading strand and in fragments on the lagging strand

What are Okazaki fragments?

• Enzymes involved in DNA replication

• Short RNA sequences synthesized by primase

• Short DNA sequences on the leading strand

• Short DNA sequences on the lagging strand

Which enzyme replaces RNA primers with DNA nucleotides?

• Helicase

• DNA polymerase III

• DNA polymerase I

• Ligase

What is the role of ligase in DNA replication?

• It proofreads the DNA sequence

• It synthesizes RNA primers

• It unwinds the DNA strands

• It joins Okazaki fragments

How fast does DNA replication occur in human cells?

• 10 base pairs per second

• 50 base pairs per second

• 100 base pairs per second

• 500 base pairs per second

What is the error rate of DNA polymerase during replication?

• 1 in 10,000 base pairs

• 1 in 10 billion base pairs

• 1 in 1,000 base pairs

• 1 in 1 million base pairs

What process allows DNA polymerase to correct its mistakes?

• Helix unwinding

• RNA priming

• Proofreading

• Mismatch repair