Main Idea:
DNA Replication –
Process of making a copy of
the DNA molecule
• Remember - for you to grow,
repair wounds or replace dead
cells, your cells must go through
mitosis
• And in order to sexually
reproduce, sex cells must be
made through meiosis.
• Before either of these processes
occur, DNA must be copied
DNA is copied
during the
Interphase’s
“S” stage
• At the origin of replication
DNA helicase enzymes
“unzip” the DNA molecule
by breaking the hydrogen
bonds between base pairs
Each strand
serves as a
template or
pattern that
complementary
nucleotides
attach to
following the
base pairing
rules
DNA polymerase enzyme joins nucleotides together
so that hydrogen bonds can form between the base
pairs to hold the 2 strands together.
DNA polymerase
also “Proofreads”
the new DNA strand
for accuracy and
corrects errors.
The base pair sequence of the 2 new DNA
molecules is identical to the original DNA molecule.
The new DNA molecule is
“semiconservative”
It is made of one strand
of the original molecule
(which served as the
template) and one newly
made strand.
There are many origins of replication
along a DNA molecule so that the
process can be completed quickly
DNA replication begins at many sites along
the long DNA molecule of a chromosome
Replication Bubbles
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The Amoeba Sister’s
DNA REPLICATION
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DNA replication
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DNA replication enzymes
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DNA replication
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