Catch Up

Question 0

What is a pesticide, give two examples

Answer 0

Chemicals that kill pests (eg insects that damage crops), some populations of mosquito evolved resistance to DDT, some populations of pollen beetles (damage oilseed rape) resistant to pyrethroid.

Question 1

Implications for humans of the evolution of pesticide resistant insects

Answer 1

1) crop infestations harder to control if insects are resistant to many pesticides. By the time farmers know which pesticide kills that insect, all crop destroyed. Or farmers may need broader pesticides, which could kill beneficial insects.
2) increased spread of disease if disease-carrying insects become pesticide-resistant
3) time and money in producing new pesticides if insects evolve resistance to ALL pesticides

Question 2

Explain the evolution of pesticide resistance

Answer 2

Natural selection

1) variation in insect population. Genetic mutation makes some insects naturally resistant to pesticide.
2) population exposed to pesticide, only individuals with resistance survive and can reproduce.
3) alleles for resistance passed on to next generation, population evolve to become more resistant.

Question 3

Explain the human implications of evolution of antibiotic resistance

Answer 3

Resistant bacteria means those infections harder to treat. Patient could die within time of identifying working antibiotic. Time and money to develop new antibiotics if bacterium develops resistance to all known antibiotics.

Question 4

What is an antibiotic, give an example?

Answer 4

A drug that kills/inhibits growth of bacteria eg MRSA is a strain of bacteria resistant to methicillin