Unit 8 - Topic 2 - DNA Replication

Multiple Choice

What is the main purpose of DNA replication?

• To prepare for mitosis by copying DNA

• To make RNA

• To break down old DNA

• To create proteins

Multiple Choice

During which part of the cell cycle does DNA replication occur?

• G1 phase

• G2 phase

• S phase

• M phase

Multiple Choice

Which enzyme unzips the DNA double helix?

• Ligase

• Helicase

• Primase

• Topoisomerase

Multiple Choice

What problem does topoisomerase solve during replication?

• Base pairing errors

• Primer removal

• 
  Supercoiling ahead of the replication fork

• Sealing Okazaki fragments

Multiple Choice

DNA is always synthesized in which direction?

• 3′ → 5′

• 5′ → 3′

• Random

• In both directions

Multiple Choice

Which enzyme adds DNA nucleotides to the growing strand?

• DNA Polymerase III

• DNA Ligase

• Exonuclease

• RNA Polymerase

Multiple Choice

What would happen if ligase didn’t do its job?

• Primers wouldn’t be added

• The DNA strands would stay tangled

• Replication would start early

• DNA fragments would remain unconnected

​Replication simulation

• Kahn Academy: Molecular mechanism of DNA replication (article) | Khan Academy​

• Class Video Link: DNA replication - 3D – YouTube​

• Amoeba Sisters: DNA Replication (Updated) – YouTube​

​Resources