Variety of Living Organisms

(3)

Another characteristic shown by animals is the ability to respond to their surroundings.

For example, a person may withdraw their hand from a hot object.

Describe the sequence of events that cause this response. (5)

m1: receptor m2: sensory neurone m3:impulse m4:CNS m5: synapse m6:relay neurone m7:motor neurone m8:muscle / effector m9: contract

Some antibiotics are no longer effective in killing pathogens.

Use your knowledge of natural selection to explain why. (5)

m1: mutation m2:.variation m3:.gene / allele / DNA m4:.survive / not killed m5: resistant m6:reproduce m7:pass on gene

The use of a pesticide may result in an increase in the number of pest organisms that are resistant to the pesticide.

Use your knowledge of natural selection to explain the increase in the number of pest organisms that are resistant to the pesticide.(5)

m1:variation m2: rare / random m3: mutation m4: gene m5: survive m6: reproduce m7: pass on (gene) m8: many generations / repeated over time /