DNA replication Flashcards
1
Q
Steps of DNA replication
A
- DNA helix ash attaches to DNA and hydrogen bonds break between base pairs. Polynucleotide strands separate
- Free nucleotides line up w complementary bases and are held together by hydrogen bonds
- DNA polymerase attaches and moves down the molecule catalysing formation of phosphodiester bond
2
Q
What are the new nucleotides called and why
A
Activated nucleotides - they have 3 phosphate groups and 2 leave to provide energy for reaction w polymerase
3
Q
Step 1 of dna replication
A
DNA helicase attaches to dna and breaks hydrogen bonds between base pairs
Strands separate
4
Q
Step 2 of DNA replication
A
Free nucleotides line up w complementary bases and held together w hydrogen bonds
5
Q
Step 3 of DNA replication
A
DNA polymerase attaches and moves down the molecule catalysing formation of phosphodiester bonds with condensation reactions
6
Q
What’s semi conservative
A
When the DNA molecule has one original strand and one new one
7
Q
What’s a mutation
A
When an incorrect base is inserted into a growing polynucleotide strand
