DNA Replication

Question 1

What are the 4 requirements for Semi-Conservative replication to be able to take place?

Answer 1

• Free nucelotides
• Template (Both strands of DNA will act as the template)
• Enzymes
• Energy

Question 2

What is the function of the enzyme ‘Helicase’?

Answer 2

To unwind the DNA and break down the hydrogen bonds between the nucleotides in each strand

Question 3

Describe the steps that take place in Semi- Conservative replication

Answer 3

1. The enzyme ‘DNA Helicase’ breaks the hydrogen bonds that link the base pairs of DNA
2. The double helix unwinds and seperates into its 2 strands.
3. Free nucleotides that have been activated bind to thier complimetary bases
4. The enzyme ‘DNA Polymerase’ joins nucelotides through a condensation reaction which makes phosphodiester bonds.
5. All the nucleotides are joined to form a polynucleotide chain
6. Two identical moleucles of DNA are formed

Question 4

What is the function of the enzyme ‘Polymerase’?

Answer 4

To join adjacent nucelotides together in a condentsation reaction which forms phosphodiester bonds