AQA GCSE Combined Science Foundation (8464), Foundation tier · Biology › Inheritance, variation and evolution › Variation and evolution
Practise Genetic engineering. 4 exam-style questions plus unlimited generated ones on this subtopic, at up to four difficulty levels, with full mark schemes and a progress tracker. Free, no account needed.
Genetic engineering modifies an organism's genome by introducing a gene from another organism to give a desired characteristic, for example bacteria that make human insulin and GM crops. Everyone needs the uses, benefits, risks and objections.
Key facts
Genetic engineering = introducing a gene from another organism to give a desired characteristic
Bacteria engineered to make human insulin (to treat diabetes)
GM crops: resistant to insects, herbicides or disease; bigger fruits; increased yields
Concerns: effects on wild flowers and insects; effects of eating GM crops on health not fully explored
Notes
What genetic engineering is
Genetic engineering is modifying the genome of an organism by introducing a gene from another organism to give a desired characteristic.
Bacterial cells have been genetically engineered to produce useful substances such as human insulin to treat diabetes.
Plant crops have been genetically engineered to be resistant to diseases or to produce bigger, better fruits.
Crops that have had their genes modified in this way are called genetically modified (GM) crops. They include crops resistant to insect attack or to herbicides. GM crops generally show increased yields.
Medical research is exploring the possibility of genetic modification to overcome some inherited disorders.
Benefits, risks and objections
Benefits: bigger yields from the same land; less of the crop lost to pests or disease; medicines such as insulin made in large amounts; possible future treatments for inherited disorders.
Concerns about GM crops include their effect on populations of wild flowers and insects.
Some people feel the effects of eating GM crops on human health have not been fully explored.
Other objections: genes could spread from GM crops to wild plants (e.g. producing herbicide-resistant weeds), and some people think it is wrong to change an organism's genes.
Don’t lose marks
Confusing genetic engineering with selective breeding or cloning.
Giving vague objections such as 'it's unnatural' without explaining a possible effect (on wild flowers, insects or health).
More tips
Memory tricks
GM crop concerns: wild flowers, insects, human health.
Exam technique
In 'evaluate' questions, give both sides and a conclusion supported by the information given.
Say that the gene comes 'from another organism'.
What each grade needs
What you need to be able to do, from the first marks up to the top grade.
Grade 4
Define genetic engineeringModifying an organism's genome by introducing a gene from another organism to give a desired characteristic.
Grade 4
Give examples of genetic engineeringBacteria that make human insulin; crops resistant to disease, insects or herbicides; bigger, better fruits.
Grade 5
State what GM crops areCrops whose genes have been modified by genetic engineering; they generally give increased yields.
Quick recall
Cover the answers and test yourself. The app has these as flashcards that come back just before you'd forget them.
Bacteria have been genetically engineered to produce a substance used to treat diabetes. Name this substance.
(Human) insulin
Sample questions
Written for this site in the style of AQA exam questions. They are not taken from real past papers.
Question 1Easy5 marks
Genetic engineering is used in agriculture and in medicine.
(a) What is genetic engineering? Tick (✓) one box.[1]
Breeding organisms with desired characteristics over many generations
Growing new plants from small groups of cells
Modifying the genome of an organism by introducing a gene from another organism
Producing identical copies of an adult animal
(b) Bacteria have been genetically engineered to produce a substance used to treat diabetes. Name this substance.[1]
(c) Which two characteristics have crop plants been genetically engineered to have? Tick (✓) two boxes.[2]
Ability to grow without light
Ability to grow without water
Resistance to herbicides
Resistance to insect attack
Ability to make their own mineral ions
(d) What name is given to crops whose genes have been modified by genetic engineering?[1]
Show the answer and mark scheme
(a)Answer: Modifying the genome of an organism by introducing a gene from another organism
(b)Answer: (Human) insulin
(human) insulin
(c)Answer: Resistance to herbicides; Resistance to insect attack
(d)Answer: Genetically modified (GM) crops
genetically modified / GM (crops)
Question 2Medium5 marks
A type of salmon has been genetically engineered with a growth-hormone gene from another species of fish. The genetically modified (GM) salmon reach the size at which they are sold in about 18 months, compared with about 36 months for ordinary farmed salmon.
(a) Calculate the percentage decrease in the time taken to reach the size at which the salmon are sold.[2]
(b) Suggest one advantage to a fish farmer of growing the GM salmon.[1]
(c) GM salmon are only allowed to be farmed in tanks on land, not in cages in the sea. Suggest why.[2]
Show the answer and mark scheme
(a)Answer: 50%
(36 − 18) ÷ 36 × 100
50 (%)
(b)Answer: More fish can be produced each year from the same tanks
more fish can be produced in a year / the fish can be sold sooner / less food and space is needed per fish sold
(c)Answer: To stop the GM salmon escaping into the sea, where they could breed with wild salmon and pass on the gene, or compete with wild fish
to stop GM salmon escaping into the wild
where they could breed with wild salmon and pass on the gene / compete with wild fish for food, affecting wild populations