GM crops: advantages and disadvantagesSpec 21.3.4
In short
GM crops are crop plants such as soya, maize and rice that have been genetically modified, for example herbicide-resistant soya, insect-resistant maize and golden rice. Advantages include higher yields, less insecticide and better nutrition. Disadvantages include genes spreading to wild plants, harm to other organisms, expensive seed and pests becoming resistant to the toxin.
Crops such as soya, maize and rice have been genetically modified. Examples are herbicide-resistant soya, insect-resistant maize (which makes a toxin that kills insect pests that eat it), and golden rice, which makes a substance the body converts to vitamin A.
| Advantages | Disadvantages |
|---|---|
| Higher yield, as less is lost to weeds and insect pests | Gene may spread to wild plants (for example weeds could become herbicide resistant) |
| Less insecticide needed, which saves money and reduces harm to other insects | May harm other organisms, such as non-pest insects, and reduce biodiversity |
| Improved nutrition, such as golden rice, which could help to reduce vitamin A deficiency | Seeds can be expensive, and farmers may need to buy new seed each year |
| Crops can be grown in conditions that would otherwise be unsuitable, helping to feed a growing population | Some people are concerned about eating GM food, as long-term effects on health are not fully known |
| Less time and money spent on spraying insecticide | Insect pests may become resistant to the toxin made by the crop |
For 'discuss', give at least one advantage and one disadvantage, and name a crop with its modification, for example insect-resistant maize.
Quick check
Define genetic modification.
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Changing the genetic material of an organism by removing, changing or inserting individual genes.
Give an example of a human protein made by genetically modified bacteria.
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Insulin.
Supplement Which enzyme cuts DNA to leave sticky ends?
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A restriction enzyme.
Supplement Which enzyme joins the gene into the plasmid?
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DNA ligase.
Supplement Name one disadvantage of GM crops.
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The gene may spread to wild plants; or it may harm other organisms.
Written and checked against the Cambridge IGCSE Biology (0610) specification · Updated October 2026