Skip to main content
Back

DNA Polymerases quiz

Control buttons has been changed to "navigation" mode.
1/15
  • What is the primary function of DNA polymerases?
    DNA polymerases are enzymes responsible for synthesizing new DNA strands during DNA replication.
  • In which direction do DNA polymerases synthesize new DNA strands?
    DNA polymerases always build new DNA strands in the 5' to 3' direction.
  • What two things are required for DNA polymerases to begin DNA synthesis?
    DNA polymerases require a template strand and a primer to initiate DNA synthesis.
  • Which enzyme provides the primer needed for DNA polymerase to start synthesis?
    The enzyme primase synthesizes the RNA primer required for DNA polymerase to begin DNA synthesis.
  • What is the role of the primer in DNA replication?
    The primer provides a free 3' hydroxyl group that DNA polymerase needs to elongate the new DNA strand.
  • Which DNA polymerase is primarily responsible for elongating new DNA strands in prokaryotes?
    DNA Polymerase III is the main enzyme responsible for elongating new DNA strands in prokaryotes.
  • What is the function of DNA Polymerase I during DNA replication?
    DNA Polymerase I replaces the RNA primers with DNA on the newly synthesized strand.
  • How do DNA polymerases distinguish between the old and new DNA strands?
    DNA polymerases distinguish old and new DNA strands based on methylation; old strands are methylated, while new strands are initially unmethylated.
  • Which bases are most commonly methylated on the old DNA template strand?
    Cytosine and adenine residues are the bases most commonly methylated on the old DNA template strand.
  • Why can't DNA polymerase start synthesizing a new DNA strand from scratch?
    DNA polymerase cannot start from scratch because it requires a free 3' hydroxyl group provided by a primer to add new nucleotides.
  • What does the term 'anti-parallel' mean in the context of DNA structure?
    Anti-parallel means that the two DNA strands run in opposite directions, with one strand oriented 5' to 3' and the other 3' to 5'.
  • What functional group is found at the 3' end of a DNA strand?
    A free hydroxyl (OH) group is found at the 3' end of a DNA strand.
  • What functional group is found at the 5' end of a DNA strand?
    A free phosphate group is found at the 5' end of a DNA strand.
  • What is methylation, and what group is added during this process?
    Methylation is the addition of a methyl group (CH3) to DNA bases, typically cytosine or adenine.
  • After DNA replication, what happens to the methylation status of the new DNA strand?
    The new DNA strand is initially unmethylated but will become methylated over time.