Presentation on theme: "Evolution and Genetic Engineering"— Presentation transcript:
1Evolution and Genetic Engineering Environmental impact on phenotype
2Environmental 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
3Environmental 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?
4Environmental 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.
5Environmental 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.
6Environmental impact on phenotype Think!Will the effects of these environmental factors be passed onto the organisms offspring?Why / why not?
7Environmental 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.
8Evolution and Genetic Engineering Natural selection
9Natural 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?
10Natural 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.
11The 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
12Natural 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
13Evolution and Genetic Engineering Selective Breeding
14Selective BreedingPeople rely on plants and animals to supply us with many of the things we need.Can you think of some examples?
15Selective 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…
16What differences can you see? Selective Breeding‘Wild’ cow‘Beef’ cowWhat differences can you see?
17Selective Breeding Note Selective breeding is the selection of individuals which possess desirable characteristics and breeding them to produce the next generation.
18Selective Breeding Notes Answer Q1+2 in Tp204 in sentencesThink!What do you think are some of the problems / limitations of selective breeding?
19Selective Breeding Notes Collect the table ‘Problems in Selective Breeding’ and use the green booklet (8.4, page 3) to complete it.
23Genetic 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)
24Advantages 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
25Advantages 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
26Genetic 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.
27Genetic 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
28Uses 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?
29Uses of Genetic Engineering Use the information on Tp to answer Tp211 ‘Testing your Knowledge’ in sentences