Hershey & Chase
determined that DNA, not proteins, was genetic material
Maurice Wilkins, Rosalind Franklin
captured image of DNA using x-ray crystallography
James Watson, Francis Crick
determined that there are 2 strands of DNA that form a double helix; phosphate+sugar=DNA backbone, and that adenine is paired with thymine, and guanine is paired with cytosine
determined that the amount of adenine=thymine; amount of guanine=cytosine
hold the DNA strand together
hold the phosphate groups and sugar in the backbone together
5 prime end
this end of the DNA strand contains a free phosphate group
3 prime end
this end of the DNA contains a free hydroxyl group
Process in which chromosomal DNA is copied before Mitosis or Meiosis
an enzyme that untwists the double helix at the replication forks, separating the two parental strands and making them available as template strands
origin of replication
Site where the replication of a DNA molecule begins, consisting of a specific sequence of nucleotides.
a region of DNA, in front of the replication fork, where helicase has unwound the double helix
a Y-shaped point that results when the two strands of a DNA double helix separate so that the DNA molecule can be replicated
an enzyme that produces an RNA primer in the 5'-3' direction and is essential to DNA replication because DNA polymerase is unable to synthesize DNA without an RNA primer
the new continuous complementary DNA strand synthesized along the template strand in the mandatory 5' --> 3' direction
A discontinuously synthesized DNA strand that elongates in a direction away from the replication fork.
Small fragments of DNA produced on the lagging strand during DNA replication, joined later by DNA ligase to form a complete strand
An enzyme that catalyzes the elongation of new DNA at a replication fork by the addition of nucleotides to the existing chain; it proofreads as it synthesizes
DNA polymerase 2
an enzyme that removes the RNA primers and replaces them with DNA nucleotides
nucleotide excision repair
The process of nuclease removing and then correctly replacing a damaged segment of DNA using the undamaged strand as a guide.
An enzyme that hydrolyzes DNA and RNA into their component nucleotides; takes out the mis-matched DNA in nucleotide excision repair
an enzyme that eventually joins the sugar-phosphate backbones of the Okazaki fragments; catalyzes the covalent bonding of the 3' end of a new DNA fragment to the 5' end of a growing chain.