Evolution: Natural Selection

Question 1

How do organisms adapt to their environment?

Answer 1

Evolution is the theory used to explain how organisms adapted to their environment.

Question 2

What is evolution?

Answer 2

Evolution is the gradual change of species over time, resulting in the formation of new species and the extinction of some others.

Question 3

Summarise the theory of natural selection to explain evolution.

Answer 3

1. Animals have a large number of offspring.
2. These offspring are different and show variation - they could be different colours or have different features.
3. A chance mutation happens and causes a different characteristic which is an advantage - they could be able to reach more food.
4. The offspring with the mutation will mate, pass on the good gene to the next generation.
5. Others without the gene won’t mate and therefore will die out.
6. Overtime a new species is formed.

Question 4

What are the stages that explain the natural selection of warfarin-resistant rats.

Answer 4

1. A mutation occurred in a gene.
2. The mutation is useful.
3. rats with the mutation survive to reproduce.
4. The useful mutation is passed on to the offspring.
5. as a result, there is an increase in the population of rats with the mutation.

Question 5

Natural selection as a rule takes a long time but sometimes under the right conditions it can happen very quickly. Name an example of this.

Answer 5

Superbugs.

Question 6

Explain superbugs.

Answer 6

Some microbes can withstand antibiotics that would usually be used to treat diseases. The antibiotics kill most of the bacteria but some have a mutation that allows them to withstand the antibiotics. As a result the antibiotics do not kill them and they can multiply to produce ‘superbugs’.