IB Biology HL 4.2.11 Pyramids of energy and trophic efficiency Question Bank

pyramid of energy shows the flow of energy from one trophic level to the next (in a community);
units of pyramids of energy are energy per unit area per unit time $/ \mathrm{kJ} \mathrm{m}^{-2} \mathrm{yr}^{-1}$; bar width is proportional to the energy stored (in the biomass) in that trophic level; the first/lowest trophic level is producers; second level is primary consumers/herbivores;
third level of secondary consumers/carnivores; only a small amount (10 to 20 % ) of energy of one level is passed to the next; bar width/energy stored in the trophic level decreases (proportionally) as you go up each level; pyramid shows that there is a limit to the length of food chains;

Marking guidance:

Award any of the above marking points to a correctly drawn and clearly labelled pyramid.