Isolating Genes

Question 1

Describe 3 enzymes/methods for isolating genes

Question 2

PCR steps

Question 3

How are marker genes used

Answer 3

Markers are added to the gene/plasmid
• These are usually, fluorescent, antibiotic resistance or enzymes
* They indicate that the coloned gene has been correctly taken up and can be expressed (protein made).
• There are variations on how this can be done, but may come up as A02. The answer will be the same:
• Eg. Colonies with the gene inserted will be resistant to antibiotics

Question 4

PCR steps

Answer 4

1-95C DNA is separated into single strands
2 - 55C Primers anneal (bind) gives
Tag somewhere to bind
3 - 72C Extension the Taq
Polymerase copies the DNA section