Bio DNA Replication

Why is DNA replication important?

Cells that divide must pass exact copies to new cells (before a cell divides, it must duplicate its DNA to pass to the new cells)

Where does DNA replication occur?

the nucleus where it is stored

DNA helicase

an enzyme that unwinds and unzips the double helix

What do the separated strands of DNA act as?

a template

What is a primer?

a short piece of RNA (produced by an enzyme called primase) that binds to the end of the leading strand

What does DNA polymerase do?

adds DNA nucleotides to a growing strand

Where does replication happen on the DNA?

at many points along separated chains

What can cause mistakes?

• mutations

• environmental factors

What does DNA polymerase do to try to avoid mistakes?

it “proofreads” DNA

Where do differences in characteristics come from?

differences in the nucleotide sequence (the order of A, T, G, and C)

What happens once replication is complete?

DNA ligase will join the two DNA strands together