Section C Answer either question 8 or question 9. This is a simple food chain: tree → insect → bird → fox

Mark scheme

Marking points from the official mark scheme (May/June 2017). The mark or mark type is shown in brackets.

1. [2] (a) standard pyramid shape with 4 levels; correctly labelled 'tree' + 'insect' + 'bird' + 'fox';
2. [4] (b) 1 not all insects / not all parts of insect + eaten (by birds); 2 (therefore) energy remains in insects (not eaten); 3 not all parts of insect digested / some lost as faeces / egested (by birds); 4 (insects) release AW energy in respiration; any two uses of energy (by insects) from the following: 5 (electrical) impulses ; 6 active transport; 7 movement / muscle contraction; 8 heat (production / loss);
3. [4] (c) 1 pyramid with 5 levels + 'flea' level at top; 2 'flea' level larger than + immediately above 'fox' level ; 3 'fox' level smaller than + immediately above 'bird' level ; 4 'bird' level smaller than + immediately above 'insect' level ; 5 'tree' level at bottom + of smallest width;