A GM crop produces a toxin that kills most insect pests. After several years, a larger proportion of the pests survive. The amount of toxin produced by the crop has not changed.
Which explanation is most likely?
Resistant insects survived and passed resistance alleles to their offspring.
Non-resistant insects produced resistant offspring because the crop needed protection.
Individual insects became resistant because the toxin changed their genes when needed.
The crop passed its toxin-producing gene to insects when they fed on its leaves.
44 exam-style questions on Edexcel GCSE Biology 4.3 Selective breeding and genetic modification, covering 4.3.1 Selective breeding and its impact, 4.3.2 Tissue culture, 4.3.3 Genetic engineering overview, 4.3.4 Main stages of genetic engineering, 4.3.5 Advantages and disadvantages of GM organisms, 4.3.6 Agricultural solutions for a growing population, and 4.3.7 Evaluating genetic engineering and breeding. Each one has a worked solution and a mark scheme showing where the marks go.