Insulin production: human insulin gene cut from human DNA → inserted into bacterial plasmid → bacteria express the gene → produce human insulin → harvested for diabetics.
Advantages over animal insulin: identical to human insulin, can be produced in large quantities, no animal welfare concerns.
GM crops and gene therapy
GM crops — crops modified to be resistant to pests (Bt crops), herbicide-resistant, drought-resistant, or with enhanced nutrition (Golden Rice — high vitamin A).
Gene therapy — replacing or correcting faulty alleles in cells. Currently experimental. Could treat inherited disorders like cystic fibrosis.
Cloning: adult cell cloning (Dolly the sheep) — nucleus from adult cell → egg cell with nucleus removed → embryo → surrogate.
⚡ Extended questions included. Read the hint. Write in full sentences. AI marks against the AQA mark scheme.
1 markInsulin productionAQA 8461 P2 style
How is genetic engineering used to produce human insulin?
A Human insulin is extracted from pigs and purified for human use
B The human insulin gene is cut out and inserted into bacterial plasmids; the bacteria then produce human insulin
C Human insulin is synthesised chemically in a laboratory without using any biological material
D Insulin-producing cells from human donors are cloned and grown in culture
1 markGM crops evaluationAQA 8461 style
Which is a genuine concern about growing GM herbicide-resistant crops?
A GM crops always produce lower yields than conventional crops
B Herbicide resistance genes could spread to wild plant species via pollen, creating "superweeds"
C GM crops produce toxins that accumulate in the food chain
D GM crops require more pesticide than conventional crops
4 marksGene therapy discussionAQA 8461 P2 style
Gene therapy could potentially be used to cure inherited disorders like cystic fibrosis. Discuss the potential benefits and ethical concerns of using gene therapy. (4 marks)
Hint: Give at least 2 benefits AND 2 concerns. Use specific examples (cystic fibrosis). Balance is essential — do not just list one side.