Extended answer - Isolation and Mutation / Selection

Question 1

Isolation and mutation 1, 2 and 3

Answer 1

1. Isolation barriers prevent gene flow between populations and preven them interbreeding.
2. Geographical isolation leads to allopatric speciation.
3. Behavioural isolation leads to sympatric speciation.

Question 2

Isolation and mutation 4, 5 and 6

Answer 2

4. Ecological isolation leads to Sympatric speciation.
5. Different mutations occur on each side of the isolation barrier.
6. Some mutations may provide a selective advantage.

Question 3

Selection 1 and 2

Answer 3

1. Natural selection is non random increase in frequency of genetic sequences that increase survival.
2. There are different selection pressures each side of a barrier.

Question 4

Selection 3 and 4

Answer 4

3. and 4. Name and description of each type of selection- disruptive, stabilising and directional.

Question 5

Selection 5, 6 and 7

Answer 5

5 and 6. After many generations an new species form

7. If populations can no longer interbreed to produce fertile offspring the different species has been produced.