Transcript DNA the Molecule of molecules - Foothill Technology High

Warm-up
When do you think DNA needs
to replicate in a cell?
DNA Replication
1. Rapid
a. In bacteria, 500 nucleotides
are added per second.
b. In human cells, it takes only
a few hours to copy the 6
billion bases.
2. Accurate
Only about 1 in a billion base
pairs is incorrectly paired.
Steps of Replication
1. The strands unzip and unwind with the
help of several enzymes.
2. Proteins bond to specific sites on DNA
called origins of replication.
3. DNA polymerase moves down the
strands, inserting the correct base to pair
with each half of DNA molecule.
4. “Proofreading enzymes” double check
the new strands, then the strands “zip
up” and two new DNA molecules are
present.
DNA Extraction Lab