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Genes can be transferred from one species to another in different ways - VCE - SSCE Biology - Question 4 - 2003 - Paper 1
Question 4
Genes can be transferred from one species to another in different ways. One method is to use plasmids, circular pieces of DNA found in some bacteria. In this method,... show full transcript
Worked Solution & Example Answer:Genes can be transferred from one species to another in different ways - VCE - SSCE Biology - Question 4 - 2003 - Paper 1
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Step 4
Explain why one of the foreign genes inserted in this way would, in general, code for resistance to a particular antibiotic. This role is important in identifying bacteria that have taken up the plasmid.
Answer
Including a gene for antibiotic resistance in the plasmid allows for the identification of bacteria that have successfully taken up the plasmid. When the bacteria are incubated on media with antibiotics, only those that have incorporated the plasmid will grow, making it easy to select for successful transformations.
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Explain why a farmer might choose to grow a crop that was genetically engineered to be resistant to insects, rather than spray the crop with insecticide.
Answer
A farmer may prefer to grow GM crops resistant to insects because it reduces the need for chemical insecticides, leading to lower costs, decreased environmental impact, and the preservation of beneficial insects. Additionally, it can lead to a healthier ecosystem.
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Suggest one advantage for a farmer to be able to spray his crops with a herbicide.
Answer
One advantage of being able to spray crops with a herbicide is that it allows for effective weed control without harming the GM crops, thus promoting higher yields and reducing competition for nutrients and water.
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Explain why farmer Y might be concerned about the possibility of his crop being fertilised by pollen from farmer X’s crop.
Answer
Farmer Y may be concerned that if pollen from Farmer X's GM crop fertilises his non-GM plants, it could lead to unintentional cross-pollination. This may impact the integrity of his crop, potentially introduce undesired traits, and compromise his marketability as a non-GM producer.
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From the data, what conclusions can be drawn about cross-pollination and the gap between crops?
Answer
The data indicates that cross-pollination decreases as the distance between the GM and non-GM crops increases. In trials with no gap, the cross-pollination percentage is highest (10%), while increasing the gap leads to significant reductions in cross-pollination (to as low as 1% with a 5-metre gap). This suggests that maintaining adequate distances between GM and non-GM crops can significantly reduce cross-pollination.