DNA structure, phases of DNA replication -- Lecture 5 Flashcards
nucleotides consist of:
5-C sugar
phosphate group
nitrogenous base
the phosphate group is at the ___ end of the nucleotide
5’ end
the ___ is at the 5’ end of the nucleotide
phosphate group
the phosphate group is at the 5’ end of the ___
nucleotide
the OH is at the ___ of the nucleotide
3’
the ___ is at the 3’ end of the nucleotide
OH
the OH is at the 3’ end of the ___
nucleotide
if the OH is at the 2’ end of the nucleotide…
nucleotide is RNA
if the H is at the 2’ end of the nucleotide
nucleotide is DNA
phosphodiester bond formation:
DNA is only synthesized in the ___ direction by DNA polymerase enzymes
5’ to 3’ direction
phosphodiester bond formation:
DNA is only ___ in the 5’ to 3’ direction by DNA polymerase enzymes
synthesized
phosphodiester bond formation:
DNA is only synthesized in the 5’ to 3’ direction by ___
DNA polymerase enzymes
phosphodiester bond formation:
___ is only synthesized in the 5’ to 3’ direction by DNA polymerase enzymes
DNA
DNA structure:
DNA backbone is held together by covalent ___
phosphodiester bonds
DNA structure:
DNA backbone is held together by ___ phosphodiester bonds
covalent
DNA structure:
___ is held together by covalent phosphodiester bonds
DNA backbone
DNA structure:
nitrogenous bases of complimentary DNA strands are held together by ___
H-bonds
DNA structure:
1 complete turn of DNA has ___
10 base pairs
DNA structure:
the ___ has a free phosphate group attached to the 5’ carbon
5’ end
DNA structure:
the 5’ end has a ___ attached to the 5’ carbon
free phosphate group
DNA structure:
the 5’ end has a free phosphate group attached to the ___
5’ carbon
DNA structure:
the ___ has a free hydroxyl (-OH) group at the 3’-carbon
3’ end
DNA structure:
the 3’ end has a ___ at the 3’-carbon
free hydroxyl (-OH) group
DNA structure:
the 3’ end has a free hydroxyl (-OH) group at the ___
3’-carbon
DNA structure:
antiparallel
DNA strands are in opposite orientations
phases of DNA replications:
DNA replication has 3 phases:
initiation
elongation
termination
phases of DNA replications:
initiation (what is it)
starting of the process
bringing together all the necessary enzymes to replicate DNA
phases of DNA replications:
elongation (what is it)
actual process of replicating the DNA
phases of DNA replications:
termination (what is it)
make sure the process is appropriately stopped
semiconservative DNA replication:
step 1:
old DNA strands are separated
H-bonds are broken
semiconservative DNA replication:
step 2:
each old DNA strand is used as a template for a new DNA strand (Semiconservative Replication)
semiconservative DNA replication:
step 3:
the new DNA molecules are 1/2 old strand and 1/2 new strand
initiating DNA replication:
replication complex (RC) – what is it
large complex containing the enzymes needed to replicate DNA, interacts w/ the DNA
initiating DNA replication:
where do RCs bind to the DNA to begin replication?
origin of replication
initiating DNA replication:
origin of replication (ori) – what is it
sequences of DNA where replication begins
initiating DNA replication:
why do eukaryotic chromosomes have thousands of oris?
eukaryotic chromosomes are very big
multiple oris allow for a much faster replication process
chromosomes get copied beginning at several ori’s ___
simultaneously
chromosomes get ___ beginning at several ori’s simultaneously
copied
___ get copied beginning at several ori’s simultaneously
chromosomes
chromosomes get copied beginning at several ori’s simultaneously:
replication complexes bind to ___
this forms
oris
replication bubbles as replication forks move out in opposite directions
chromosomes get copied beginning at several ori’s simultaneously:
(steps)
replication complexes bind to the ori’s
DNA strands are separated
DNA replication proceeds bidirectionally
direction of replication:
DNA strands are separated at replication forks by ___
helicase
direction of replication:
DNA strands are ___ at replication forks by helicase
separated
direction of replication:
DNA strands are separated at ___ by helicase
replication forks
direction of replication:
___ are separated at replication forks by helicase
DNA strands
direction of replication:
helicase (what does it do)
breaks the H-bonds b/n strands
direction of replication:
on the ___: new DNA is synthesized continuously in the 5’ –> 3’ direction by DNA Pol III
leading strand
direction of replication:
on the leading strand: new DNA is synthesized continuously in the ___ direction by DNA Pol III
5’ –> 3’
direction of replication:
on the leading strand: new DNA is synthesized continuously in the 5’ –> 3’ direction by ___
DNA Pol III
direction of replication:
on the leading strand: new DNA is ___ in the 5’ –> 3’ direction by DNA Pol III
synthesized continuously
direction of replication:
on the lagging strand: new DNA is synthesized in discontinuous fragments in the 5’ –> 3’ direction (occurs more ___)
slowly
direction of replication:
on the lagging strand: new DNA is synthesized in discontinuous fragments in the ___ direction (occurs more slowly)
5’ –> 3’
direction of replication:
on the lagging strand: new DNA is synthesized in ___ in the 5’ –> 3’ direction (occurs more slowly)
discontinuous fragments
direction of replication:
on the lagging strand: new DNA is ___ in discontinuous fragments in the 5’ –> 3’ direction (occurs more slowly)
synthesized
direction of replication:
on the lagging strand: ___ is synthesized in discontinuous fragments in the 5’ –> 3’ direction (occurs more slowly)
new DNA
direction of replication:
on the ___: new DNA is synthesized in discontinuous fragments in the 5’ –> 3’ direction (occurs more slowly)
lagging strand
