In a grassland ecosystem, the amount of energy captured by the photosynthetic organisms was 100 000 kJ m^–2 yr^–1. Construct a pyramid of energy indicating the predicted energy levels for four trophic levels, including the producers.

Define biomass.

Values: primary consumers: 10 000 kJ m^–2 yr^–1, secondary consumers: 1000 kJ m^–2 yr^–1 and tertiary consumers: 100 kJ m^–2 yr^–1
correct values; (allow 20 % error)
correct trophic level labels; (do not accept trophic level 1, trophic level 2 etc.)
drawing showing proper proportions; (height of each step the same, each bar no more than one quarter of the one below)

the dry mass / organic material (of a group) of organisms in a given area/habitat

Most were able to correctly identify the trophic levels for one mark. Some were able to correctly give the predicted energy levels as roughly 10% of the previous level although some indicated that only 10% was used or lost so that 90% went on to the successive level.  Few drew a good pyramid of energy diagram.

Again, the definition was not clear and concise in most cases.