Presentation on theme: "Evolution and Genetic Engineering"— Presentation transcript:
1 Evolution and Genetic Engineering Environmental impact on phenotype
2 Environmental impact on phenotype An organism’s final appearance (phenotype) is the result of the interaction between it’s genotype and the environment it develops in.This can be shown as a word equation:genotype + environment = phenotype
3 Environmental impact on phenotype Studies to investigate the effect of different environmental factors on phenotype are carried out using identical twins (human) or clones (plants)Why?
4 Environmental impact on phenotype Notesgenotype + environment = phenotypeTo investigate the impact of environmental factors on phenotype, scientists can conduct twin, or clone, studies. Because the twins are genetically identical, any differences in phenotype must be due to environment.
5 Environmental impact on phenotype Notes:Give an example of how environment can influence the phenotype of human identical twins during growthGive an example of how environment can influence the phenotype of humans after growth is complete.
6 Environmental impact on phenotype Think!Will the effects of these environmental factors be passed onto the organisms offspring?Why / why not?
7 Environmental impact on phenotype NoteDifferences in phenotype caused by environmental factors (‘acquired characteristics’) are not passed down from one generation to the next.Acquired characteristics therefore have little evolutionary significance, as they play no part in natural selection.
8 Evolution and Genetic Engineering Natural selection
9 Natural Selection Think! Does every organism get a chance to pass on it’s genes?Why / why not?What could this have to do with evolution?
10 Natural Selection Notes Natural selection is the process by which organisms that are better adapted to their environment survive and breed, while those less well adapted fail to do so.So the better adapted organisms are more likely to pass their characteristics to the next generations.
11 The Peppered Moth Watch this video Now collect the cut-out of ‘The Peppered Moth Story’, and stick it – in the correct order – in your notes
12 Natural Selection Summary Sexually reproducing organisms show genetic varietySome organisms are better adapted to their surroundings than othersThis allows them to survive and pass on these favourable genes – natural selectionOver time, natural selection can result in the creation of new species - evolution
13 Evolution and Genetic Engineering Selective Breeding
14 Selective BreedingPeople rely on plants and animals to supply us with many of the things we need.Can you think of some examples?
15 Selective BreedingAll of the species of plants and animals that we eat or use today are derived from wild ancestorsHowever, some look very different. Have a look at the cows on the next slide…
16 What differences can you see? Selective Breeding‘Wild’ cow‘Beef’ cowWhat differences can you see?
17 Selective Breeding Note Selective breeding is the selection of individuals which possess desirable characteristics and breeding them to produce the next generation.
18 Selective Breeding Notes Answer Q1+2 in Tp204 in sentencesThink!What do you think are some of the problems / limitations of selective breeding?
19 Selective Breeding Notes Collect the table ‘Problems in Selective Breeding’ and use the green booklet (8.4, page 3) to complete it.
23 Genetic Engineering Notes Collect a ‘Genetic Engineering’ diagramUse Torrance p206 to fill in the missing information and stick into your notes.Then attempt Tp207 Q3(b)
24 Advantages and Disadvantages of Genetic Engineering Using the information in the green booklet 8.5 page 2+3, draw a table like the one below and complete it with 5 advantages and 3 disadvantages of genetic engineeringAdvantages of genetic engineeringDisadvantages of genetic engineering
25 Advantages of genetic engineering Disadvantages of genetic engineeringCompletely different species can be combinedOrganism shows only the desired characteristicLarge quantities can be producedEasier to purify productFaster than selective breedingBacteria can’t produce complex proteinsDifficult to insert genes without damaging host cellMight produce harmful by-productsPossible release of GM organisms into environmentExpensive
26 Genetic Engineering Vs Selective Breeding Genetic engineering and selective breeding are two methods by which scientists can alter the genotype of another species for the benefit of humankind.On the flipchart paper, compare the two methods.
27 Genetic Engineering Debate You are now going to look at some of the arguments surrounding the use of genetic engineering.Collect the sheet of statements and cut them outUse the statements to produce a table as shown on Tp213
28 Uses of Genetic Engineering Think!What was being produced using genetic engineering in the video?Where was this originally obtained?What do you think the benefits are of the genetically engineered product over that of the original source?
29 Uses of Genetic Engineering Use the information on Tp to answer Tp211 ‘Testing your Knowledge’ in sentences