screening and selecting transformed cells

Question 1

not all of the host cells (usually bacteria) will ?

Answer 1

successfully take up a recombinant plasmid

Question 2

what 3 issues may occur when the host cell does not take up the recombinant DNA ?

Answer 2

• the recombinant plasmid doesn’t get inside the cell
• the plasmid re-joins before the DNA fragment is created
• the DNA fragment sticks to itself rather than inserting into the plasmid

Question 3

therefore what must scientists do ?

Answer 3

• they must identify which bacteria successfully took up a recombinant plasmid

Question 4

what can be used to identify which bacteria successfully took up the recombinant plasmid ?

Answer 4

• marker genes

Question 5

what are the 3 different marker genes used ?

Answer 5

• antibiotic resistance genes
• genes coding for fluorescent proteins
• genes coding for enzymes