DNA Replication Flashcards
During the replication process, the two complementary
strands of DNA come apart and serve as _____ for the synthesis of 2 new strands of DNA
template or parental strands
To complete the replication process, what bond is
formed between the phosphate of one nucleotide and the sugar of the previous nucleotide?
covalent bond
how are two DNA strands linked together?
through hydrogen bonding
process by which a double-stranded DNA is copied to produce two identical DNA molecules
DNA replication
DNA replication models:
[SCD]
semiconservative
conservative
dispersive
the double-stranded DNA is half conserved following the replication process; it is a complex of an old parental strand and one daughter strand
semiconservative replication
both parental strands of DNA remain together following DNA replication; parental strands is completely conserved, and two newly made daughter strands also remain together following replication
conservative replication
segments of parental DNA and newly made DNA are interspersed in both strands following the replication process; contain a part of the old and new
dispersive replication
what is the correct model for DNA replication?
semiconservative replication
before a cell divides, DNA must first be
copied
in what phase is DNA copied?
S phase of interphase
what forms when DNA opens are the origin?
replication bubbles
replicating units that form bubbles and are stretches of DNA with a single origin of replication
replicons
synthesizes the leading strand
continuous replication
synthesizes the lagging strand
discontinuous replication
3’-5’ template strand, runs in 5’-3’ direction, replicates towards the replication fork
leading strand
5’-3’ template strand, runs in 3’-5’ direction, replicates away from the replication fork
lagging strand
short segments where the lagging strand occurs
okazaki fragments
DNA polymerase can only add nucleotides in what direction?
5’ to 3’
unzipping enzyme; unwinds the DNA double helix
helicase
initializer; synthesizes short oligonucleotides
primase
allows the leading strand to be threaded through
clamp protein
builder; join the assembled nucleotides
DNA polymerase
gluer; join okazaki fragments in the lagging strands; spot welder
ligase
fills in small DNA fragments during replication and repair
DNA polymerase I
alternative repair polymerase
DNA polymerase II
major DNA polymerase during normal DNA replication
DNA polymerase III
arrange the steps:
(a) primase creates the primers on both strands
(b) single-stranded binding proteins attach and keep the 2 DNA strands separated and untwisted
(c) DNA polymerase can add the new nucleotides
(d) helicase unwinds the DNA and separates the strands
D, B, A, C
this enzyme attaches to the 2 forks of the bubble to relieve stress on the DNA molecule as it separates
topoisomerase
alleviates positive supercoiling
topoisomerase II
the purpose of primase is to build the ______ which attracts the _______
RNA primer, DNA polymerase
this keeps the DNA strands seprated and untwisted
SSB
DNA polymerase can only add nucleotides to the __ end of the sugar
3’
arrange the steps:
(e) replication continues
(f) DNA polymerase proofreads, checks activity, and replaces incorrect bases
(g) ligase seals sugar-phosphate backbone
(h) enzymes remove RNA primers
F, E, H, G
where does energy for bonding come from?
from the nucleotides, which have three phosphates attached such as ATP
when bonds are broken, energy is released
