class notes 2: dna replication. replication process
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Class Notes 2:Class Notes 2:
DNA ReplicationDNA Replication
Replication ProcessReplication Process
Replication ProcessReplication Process
Replication ProcessReplication Process
Replication ProcessReplication Process
Replication ProcessReplication Process
Replication ProcessReplication Process
Replication ProcessReplication Process
Replication ProcessReplication Process
Replication ProcessReplication Process
Replication ProcessReplication Process
Replication ProcessReplication Process
Replication ProcessReplication Process
Replication ProcessReplication Process
Replication ProcessReplication Process
I. Why does DNA replicate?I. Why does DNA replicate?
A.A. Every new cell needs its own DNA.Every new cell needs its own DNA.
B.B. Must be identical to original.Must be identical to original.
C.C. Occurs during interphase, before mitosis.Occurs during interphase, before mitosis.
II. ReplicationII. Replication
A. Step 1-A. Step 1-
The hydrogen bonds holding the base pairs The hydrogen bonds holding the base pairs together are broken and the DNA unzips together are broken and the DNA unzips into 2 separate single strands.into 2 separate single strands.
B. Step 2 of ReplicationB. Step 2 of Replication
As the DNA is As the DNA is unzipping, each unzipping, each strand becomes a strand becomes a template.template.
Free nucleotides from Free nucleotides from the cell match with the cell match with the corresponding the corresponding base pair. They are base pair. They are bonded by DNA bonded by DNA polymerase.polymerase.
C. Step 3 of ReplicationC. Step 3 of Replication
Replication produces 2 new single Replication produces 2 new single strands, each connected to one strands, each connected to one original strand. original strand.
Since one strand is “conserved” in Since one strand is “conserved” in each new molecule of DNA, this is each new molecule of DNA, this is called semi-conservative replicationcalled semi-conservative replication
SummarySummary
List the steps of replication. Why is List the steps of replication. Why is replication necessary?replication necessary?