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Question 1

What is the process of evolution?

Answer 1

1. Variation exists within a population from genetic differences
2. An environmental change occurs which increases competition between the animals
3. Only resistant animals survive due to natural selection
4. Offspring inherit resistance
5. Occurs over many generations

Question 2

How does ardi from 4.4M years ago show evidence of evolution?

Answer 2

• fossilised skeleton contains many ‘humanoid’ features
• resembles an ape so is phenotypically somewhere between the two
• bone structures in feet is different from chimpanzees, showing two evolved separately

Question 3

How does lucy from 3.2M years ago show evidence for evolution?

Answer 3

• bone structure suggests she walked upright in a human way
• small brain represents another intermediate between apes and humans

Question 4

What is the process of genetic engineering?

Answer 4

1. Plasmid DNA removed from bacteria
2. It is cut open using restriction enzymes , leaving sticky ends
3. DNA is removed from cell nucleus of human
4. Gene that gives desired protein is cut using same restriction enzyme as plasmid to leave complimentary sticky ends
5. Ligase enzyme is used to ensure plasmid DNA and human DNA attach by forming complimentary base pairs
6. The recombinant DNA is put back into bacteria which divide rapidly