Class Notes 2:

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Class Notes 2

• DNA Replication

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Replication Process
A-T-C-G-G-T-A-T-A-C-C-G-C-T-A-T
T-A-G-C-C-A-T-A-T-G-G-C-G-A-T-A
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Replication Process
A-T-C-G-G
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T-A-G-C-C
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Enzyme
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Replication Process
A-T-C-G-G
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T-A-G-C-C
-A-T-A-T-G-G-C
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Replication Process
A-T-C-G-G
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T-A-G-C-C
-A-T-A-T-G-G-C
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Replication Process
A-T-C-G-G
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T-A-G-C-C
-A-T-A-T-G-G-C
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Replication Process
A-T-C-G-G
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T-A-G-C-C
-A-T-A-T-G-G-C
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Replication Process
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A-T-C-G-G
T-A-G-C-C
-A-T-A-T-G-G-C
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Replication Process
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A-T-C-G-G
T-A-G-C-C
-A-T-A-T-G-G-C
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Replication Process
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A-T-C-G-G
T-A-G-C-C
-A-T-A-T-G-G-C
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Replication Process
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A-T-C-G-G
T-A-G-C-C
-A-T-A-T-G-G-C
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Replication Process
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A-T-C-G-G
T-A-G-C-C
-A-T-A-T-G-G-C
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Replication Process
-T-A-T-A-C-C-G
A-T-C-G-G
T-A-G-C-C
-A-T-A-T-G-G-C
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Replication Process
-T-A-T-A-C-C-G
A-T-C-G-G
T-A-G-C-C
-A-T-A-T-G-G-C
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Replication Process
-T-A-T-A-C-C-G
A-T-C-G-G
T-A-G-C-C-A-T-A-T-G-G-C
A-T-C-G-G-T-A-T-A-C-C-G
T-A-G-C-C
-A-T-A-T-G-G-C
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I. Why does DNA replicate?

1. Every new cell needs its own DNA.
2. Must be identical to original.
3. Occurs during interphase, before mitosis.

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II. Replication

• A. Step 1-
• The hydrogen bonds holding the base pairs
  together are broken and the DNA unzips into 2
  separate single strands.

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B. Step 2 of Replication

• As the DNA is unzipping, each strand becomes a
  template.
• Free nucleotides from the cell match with the
  corresponding base pair. They are bonded by DNA
  polymerase.

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C. Step 3 of Replication

• Replication produces 2 new single strands, each
  connected to one original strand.
• Since one strand is conserved in each new
  molecule of DNA, this is called semi-conservative
  replication

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Summary

• List the steps of replication. Why is replication
  necessary?