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
Notes
genotype + environment = phenotype
To 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 growth
Give 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
Note
Differences 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 variety
Some organisms are better adapted to their surroundings than others
This allows them to survive and pass on these favourable genes – natural selection
Over time, natural selection can result in the creation of new species - evolution

13. Evolution and Genetic Engineering
Selective Breeding

14. Selective Breeding
People rely on plants and animals to supply us with many of the things we need.
Can you think of some examples?

15. Selective Breeding
All of the species of plants and animals that we eat or use today are derived from wild ancestors
However, 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’ cow
What 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 sentences
Think!
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.

20. Evolution and Genetic Engineering

21. Genetic Engineering Notes
Another method of artificial selection is genetic engineering
Genetic engineering is the transfer of DNA from one type of organism to a different organism

22. Genetic Engineering
Bacterial cell

23. Genetic Engineering Notes
Collect a ‘Genetic Engineering’ diagram
Use 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 engineering
Advantages of genetic engineering
Disadvantages of genetic engineering

25. Advantages of genetic engineering
Disadvantages of genetic engineering
Completely different species can be combined
Organism shows only the desired characteristic
Large quantities can be produced
Easier to purify product
Faster than selective breeding
Bacteria can’t produce complex proteins
Difficult to insert genes without damaging host cell
Might produce harmful by-products
Possible release of GM organisms into environment
Expensive

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 out
Use 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