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16 Cards in this Set
- Front
- Back
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Two types of Variation |
Environmental- how,where you live. How you take care of yourself Genetic- born with it cannot change it in your genes |
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How do Variants arise? |
Variants arise from mutations which is when there is a mistake when copying DNA. Most mutations don’t have an effect but some cause variation. |
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Natural selection |
Mutations occur which May cause some species to have favourable characteristics to survive in certain environmental conditions. These variants pass on their genes and eventually the whole population gains these characteristics. |
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Selective Breeding |
- Parents with favourable characteristics - Produce perfect child which breeds to form more perfect children |
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Advantages of Selective Breeding |
- Disease resistant food and crops - Cows with large milk yield and lots of meat - Large, beautiful flowers |
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Disadvantages of Selective Breeding |
- Reduces number of alleles in population - No variation so a new disease will wipe out a population - Inbreeding leads to inherited defects. |
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Genetic Engineering |
Modifying genome for favourable characteristics Ligase inserts the insulin gene into the plasmid Restriction enzyme takes small chip out of plasmid |
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Advantages of Genetic Engineering |
- Favourable characteristics can be transferred to plants => Disease resistant => More yield |
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Disadvantages of Generic engineering |
- Effects on eating GM crops are not discovered - Effect wild flowers + insects |
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Cloning Plants |
Clones - Genetically identical 3 types - Tissue culture - Cuttings - Adult Cell Cloning |
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Tissue Culture |
Using small groups of cells from part of a plant to grow identical new plants. This is important for preserving rare plant species or commercially in nurseries. |
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Cuttings |
Simple method used by gardeners to produce many identical plants from one parent plant m |
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Cuttings |
Simple method used by gardeners to produce many identical plants from one parent plant m |
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Advantages of Adult Cell Cloning |
- Genetically identical - Can save animals from extinction - Can have uses in medicine |
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Disadvantages of Adult Cell Cloning |
- Concerned about ethics - Limits variation so no adaptation i.e environment changes - Concerned about using this technique to clone humans in the future. |
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Concerns about genetic technologies |
- Farmers have to buy new seed because crops are infertile - Genes maybe spread to wild flowers - Insects may be affected by infertile crops - Insects could become resistant - Effects of eating crops - Not fair on animals or other ethical opinions |
