Synthesizes the primer
Starts a complementary RNA chain from a single RNA nucleotide, adding more RNA nucleotides one at a time, using the parental DNA strand as a template
Back
Nucleotide excision repair
Front
DNA repair system where teams of enzymes detect and repair the DNA, the nuclease cuts out the damaged DNA and removes it, fills in the missing nucleotides and the DNA ligase seals the free end of the new DNA to the old DNA making the strand complete
Back
Histones
Front
Proteins that are responsible for the first level of DNA packing in chromatin
Back
Telomeres
Front
Special nucleotide sequences at the ends of chromosomes
TTAGGG is repeated between 100-1000 times
Prevent the staggered ends of daughter molecule from activitating cell's system for monitoring DNA damage
Back
Helicases
Front
enzymes that untwist the double helix at the replication forks, separating the two parental strands and make them available as template strands
Back
DNA Replication
Front
the process by which a DNA molecule is copied; also called DNA synthesis
Back
Hershey and Chase (Don't need to memorize scientists)
Front
Concluded that phage DNA entered bacterial host cells, but phage proteins did not, so DNA functions as the genetic material
Back
Okazaki fragments
Front
Series of segments that are 1000-2000 nucleotides long
Back
DNA Ligase
Front
joins the sugar phosphate backbones of all the Okazaki fragments into a continuous DNA strand
Back
Purines
Front
A and G
Nitrogenous bases with two organic rings
Back
Primer
Front
The initial nucleotide chain that is produced during DNA synthesis is actually a short stretch of RNA
Back
Replication Fork
Front
a Y shaped region where the parental strands of DNA are being unwound
Back
Heterochromatin
Front
centromeres and telomeres exist in a highly condensed state with visible irregular clumps making it largely inaccessible
Back
Rosalind Franklin (Don't need to memorize scientists)
Front
accomplished X-ray crystallographer that discovered the double helix of DNA
Back
Conservative model
Front
two parental strands reassociate after acting as templates for new strands thus restoring the parental double helix
Back
DNA polymerases
Front
Enzyme that catalyze the synthesis of new DNA by adding nucleotides to a preexisting chain
Back
Nitrogenous bases of Dna
Front
A, T, C, G
Back
Virus
Front
infects a cell and takes over the cell's metabolic machinery
Back
Euchromatin
Front
centromeres and telomeres exist in a less compacted state that is very accessible
Back
Chargaff's Law
Front
the base compostion of DNA varies between species and for each species, the percentages of A and T bases are roughly equal to the percentages of the G and C bases
Back
Origins of Replication
Front
short stretches of DNA having a specific sequence of nucleotides
Back
Transformation
Front
a change in genotype and phenotype due to the assimilation of external DNA by a cell
transforming substance- DNA
Back
Telomerase
Front
Enzyme that catalyzes the lengthening of telomeres in eukaryotic germ cells and restores the original length and compensating for the shortening that occurs during DNA replication
Back
Nuclease
Front
DNA cutting enzyme that cuts out the damaged parts of the strand and fills the space with nucleotides using the undamaged strand as a template
Back
Chromatin
Front
complex of DNA and protein
Back
Bacteriophages
Front
Viruses that infect bacteria
Bacteria eaters
Back
Mismatch repair
Front
Other enzymes remove and replace incorrectly paired nucleotides that have resulted from replication errors
Back
Pyrimidines
Front
C and T
Nitrogenous base with a single organic ring
Back
Topoisomerase
Front
The untwisting of double helix causes tighter twisting and strain ahead of replication fork
Relieve this strain by breaking swiveling, and rejoining DNA strands
Back
Dispersive Model
Front
each strand of both daughter molecules contains a mixture of old and newly synthesized DNA
Back
Semiconservative Model
Front
the two strands of the parental molecule separate and each functions as a template for synthesis of a new complementary strand- most common
Back
Single Strand Binding Proteins
Front
Bind to the unpaired DNA strands keeping them from repairing
Back
Griffith (Don't need to memorize scientists)
Front
Concluded that nonpathogenic bacteria transformed into pathogenic bacteria by an unknown, heritable substance from the dead S cells that enabled the R cells to make capsules
Back
Nucleosome
Front
the basic unit of DNA packing
Back
Leading strand
Front
Strand that continuously adds nucleotides to the new complementary strand as the fork progresses
DNA pol III
Back
Antiparallel
Front
subunits run in opposite directions
Back
DNA pol III
Front
Synthesizes new DNA strands by adding nucleotides to an RNA primer or a pre-existing DNA strand
Back
DNA pol I
Front
Removes RNA nucleotides of primer from 5' end and replaces them with DNA nucleotides
Back
Lagging Strand
Front
The strand that DNA pol III works away from the replication fork
Synthesized discontinuosly as a series of segments