DNA Replication and Repair Quiz

What is a replisome?

• A type of DNA polymerase

• A complex of enzymes involved in DNA replication

• A type of RNA primer

• A single-stranded DNA molecule

Which DNA polymerase is primarily responsible for leading strand synthesis?

• DNA Polymerase I

• DNA Polymerase IV

• DNA Polymerase II

• DNA Polymerase III

Which of the following is NOT a requirement for DNA polymerization?

• RNA polymerase

• Mg²⁺ ions

• DNA building blocks

• Presence of a primer

What type of repair mechanism is used to fix mismatched bases in DNA?

• Base-excision repair

• Nucleotide-excision repair

• Mismatch repair

• Nonhomologous end-joining

What is the role of telomerase in DNA replication?

• To synthesize RNA primers

• To unwind the DNA double helix

• To add repetitive DNA sequences to chromosome ends

• To repair mismatched bases

Which is the key enzyme is involved in base-excision repair?

• DNA ligase

• DNA glycosylase

• DNA helicase

• DNA polymerase III

What is the primary consequence of telomere shortening?

• Increased mutation rates

• Cellular aging and death

• Enhanced DNA repair

• Improved genetic diversity

Which of the following proteins is involved in homologous recombination in E.coli?

• DNA ligase IV

• RecA

• Ku70/80

• DNA polymerase I

What is the main role of the RecBCD enzyme complex in E. coli?

• To initiate DNA replication

• To prepare DNA for strand exchange during recombination

• To repair mismatched bases

• To synthesize telomeres

Which of the following occurs in retroviruses?

• DNA is replicated in the 3' → 5' direction.

• DNA is replicated in the 5' → 3' direction.

• DNA is transcribed to RNA.

• RNA is reverse-transcribed to DNA.