Population and Evolution

Question 1

suggest an explanation for the results in the figure?

Answer 1

• mutation produces KDR minus allele
• DDT use provides selection pressure
• KDR minus allele in pop inc
• those with KDR minus survive, reproduce and pass on allele
• frequency of KDR minus inc in pop

Question 2

Answer 2

• neurones remain depolarised
• no AP

Question 3

Answer 3

• sodium ion channel protein changes shape
• DDTs shape no longer complementary

Question 4

lord howe island in the Tasman Sea possesses two species of palm tree which have arisen via sympatric speciation.

the 2 species diverged from each other after the island was formed 0.5 million years ago. the flowering times of the 2 species are different.

use this info to suggest how the 2 species of tree arose by sympatric speciation?

Answer 4

• occurs in same habitat/population
• mutations cause diff flowering times
• reproductive isolation
• different alleles passed on
• disruptive natural selection
• eventually different species cannot interbreed to produce fertile offspring