DNA Replication Processes and Enzymes

Mr. Kenny explains DNA replication, highlighting the unwinding of DNA by helicase, the creation of complementary strands by DNA polymerase, and the distinction between leading and lagging strands. He discusses the role of various enzymes, including ligase and primase, and addresses chromosome erosion and telomeres. The video concludes with a summary of the replication process and how DNA is packed into chromosomes.

What is the role of helicase in DNA replication?

• It synthesizes new DNA strands.

• It unwinds the DNA double helix.

• It joins Okazaki fragments.

• It replaces RNA primers with DNA.

Which enzyme is responsible for adding nucleotides to the growing DNA strand?

• DNA Polymerase III

• Primase

• Helicase

• Ligase

What are Okazaki fragments?

• Short DNA sequences on the leading strand

• Short DNA sequences on the lagging strand

• Proteins that unwind DNA

• Enzymes that synthesize DNA

What is the function of ligase in DNA replication?

• It unwinds the DNA double helix.

• It synthesizes RNA primers.

• It adds nucleotides to the DNA strand.

• It joins Okazaki fragments.

Why are RNA primers necessary in DNA replication?

• They replace DNA nucleotides.

• They join Okazaki fragments.

• They unwind the DNA double helix.

• They provide a starting point for DNA synthesis.

What is the role of DNA polymerase I in DNA replication?

• It replaces RNA primers with DNA.

• It unwinds the DNA double helix.

• It joins Okazaki fragments.

• It synthesizes new DNA strands.

What problem does chromosome erosion pose during DNA replication?

• It stops the synthesis of new DNA strands.

• It prevents DNA from unwinding.

• It leads to the loss of genetic information.

• It causes DNA strands to break.

How do telomeres help in DNA replication?

• They join Okazaki fragments.

• They prevent the loss of genetic information.

• They synthesize new DNA strands.

• They unwind the DNA double helix.

What is the approximate speed of DNA polymerase III?

• 100 bases per second

• 10 bases per second

• 1000 bases per second

• 10000 bases per second

How is DNA packed into chromosomes?

• By winding around histones

• By forming Okazaki fragments

• By synthesizing RNA primers

• By joining with ligase