Genetic Modification Flashcards
How can microorganisms be modified
Using restriction enzymes the circular plasmid is cut and using another set of enzymes a piece of DNA from another species can be spliced into it and the plasmid inserted back into the bacteria which are allowed to multiply in a fermenter and the protein produced is extracted and purified
What is artificial selection
The selection of alleles for characteristics that are agriculturally valuable
What is a genetically modified plant
A plant who’s DNA contains new genes with alleles for desired characteristics
How can genes be inserted into plant cells
-bacterium that infects species of plant can be used, when the bacteria invade plant cells genes from plasmid (vector) DNA become incorporated into the chromosomes of the plant cells
-minute pellets covered with DNA carrying the desired genes shot into plant cells using particle gun
-viruses used which infect cells and insert their DNA/RNA
How are plants screened to find out if they have the new gene
Incorporate a gene for antibiotic resistance (marker gene) along with the new desired gene, the antibiotic is toxic to plant cells at a high enough dose so plant cells incubated with the antibiotic which kills off any cells that have not taken up the new genes
What is micropropagation
How the genetically modified plant cells are grown in Agar in sterile conditions with nutrients and plant growth substances to produce new plants
How can animals be genetically modified
Inject DNA directly into the nucleus of a fertilised egg, then implanted into surrogate female/ use retroviruses
Health concerns about genetic modification
-transfer of antibiotic resistance genes to microbes
-formation of harmful products by new genes
-transfer of viruses from GM animals to humans
How could GM crops cause antibiotic resistance
As they contain marker gene for antibiotic resistance which when the crop is eaten the gene could be transferred to pathogenic microbes in the gut which could build up resistance to certain antibiotics used in medical treatments
Environmental issues of GM crops
-transfer of genes to non-target species (eg wild plants and conventional crops)
-can cause weeds to become resistant to pesticides/drought (if genes transferred to weeds)
-may lead to the increased use of chemicals in agriculture to control resistant weeds
Ethical issues surrounding ownership of GM crops
-developing countries unlikely to be able to afford to pay for expensive licences to use the new technology to grow GM crops
-farmers in poorer countries where there are frequent food shortages cannot afford to invest in pricey seeds and when they sell their traditional crops may have to compete with cheaper/higher quality products from GM varieties
