Miscellaneous I
A specific sequence of RNA nucleotides used as a starting point for the replication of the new DNA strands.
What is the primer?
Both DNA strands will always grow towards this despite the direction of replication.
What is the replication fork?
Two DNA strands winding up around each other.
What is the double-helix?
Enzyme the connects to the RNA primer to start the replication process.
What is DNA polymerase?
Method of replication used by the lagging strand.
What is the back-stitching replication method?
A phosphate group + deoxyribose + one of 4 nitrogenous bases (adenine, guanine, cytosine and thymine).
What is a DNA nucleotide?
The rate of mutation for proofread DNA.
What is 1 in 100 million base-pairing errors?
Type of cell that needs to undergo DNA replication.
What is a mitotic cell (a dividing cell)?
The phase in the cell cycle in which DNA replication takes place.
What is the S (synthesis) phase?
Mismatches in the DNA complementary base-pairing system.
What are mutations?
Y-shaped region.
What is the replication fork?
Names for the old strands and the new strands, respectively.
What are parental and daughter strands?
Enzyme that breaks the hydrogen bonds between the nitrogenous bases unzipping the DNA strands in a DNA double-helix.
What is helicase?
Proteins that keep the 2 DNA strands separated by preventing the hydrogen bonds from reforming.
What are single-strand binding proteins?
Enzyme that releases the stress at the fork to prevent coiling back of the DNA molecule.
What is topoisomerase?
Enzyme that synthesizes the RNA primer.
What is primase?
Enzyme that adds the new DNA nucleotides after the RNA primer to make the new daughter strand.
What is DNA polymerase?
Direction in which new strands are being built.
What is the 5'- 3' direction?
Short segments: RNA primer and DNA nucleotides.
What are Okazaki fragments?
It is synthesized discontinuously against the overall direction of DNA replication.
What is the lagging strand?
It joins the Okazaki fragments together once RNA primers are replaced by DNA nucleotides.
What is DNA ligase?
It removes the RNA nucleotides segments called primers.
What are exonucleases?
Enzymes that repair damaged DNA caused by UV radiation or harmful chemicals.
What are excision repair enzymes?
Mechanism that corrects mismatches/mispairings between the nitrogenous bases.
What is DNA proofreading?
Type of DNA replication originally proposed by Watson and Crick in which each of the two old strands serves as a template for a new strand.
What is semiconservative replication?