In an intensive poultry farming system, broiler chickens are fed on high-protein soy meal.
It requires 5 kg5\text{ kg}5 kg of soy meal to produce 1 kg1\text{ kg}1 kg of chicken biomass. Explain why 5 kg5\text{ kg}5 kg of soy meal only yields 1 kg1\text{ kg}1 kg of chicken biomass.
Biotechnologists are researching ways to genetically modify soy crops so they produce higher concentrations of methionine (an essential amino acid), reducing the need for synthetic dietary supplements in poultry feed.
Explain how restriction endonucleases and DNA ligase are used to insert a desired gene into a host organism's DNA.
Describe the role of a named vector in this genetic modification process.
30 exam-style questions on Edexcel IGCSE Biology Genetic modification (genetic engineering). Each one has a worked solution and a mark scheme showing where the marks go.