In genetic engineering, the useful gene and an antibiotic resistance gene are put into the same plasmid. Why are they put into the same plasmid?
The marker gene switches on the useful gene when the bacteria divide.
The antibiotic cuts the plasmid open so the useful gene can enter.
Bacteria with the marker gene make antibodies against the antibiotic.
Bacteria that survive the antibiotic must also contain the useful gene.
127 exam-style questions on OCR GCSE Biology 6.2 Feeding the human race, covering 6.2.1 Biological factors affecting food security, 6.2.2 Agricultural solutions to growing demand, 6.2.3 Selective breeding, 6.2.4 Genetic engineering, 6.2.5 Steps in genetic engineering, 6.2.6 Benefits and risks of gene technology in agriculture, and 6.2.7 Biotechnological solutions to growing demand. Each one has a worked solution and a mark scheme showing where the marks go.