B2(i) - Life Processes 9.

Pyramids of Number and Biomass.

A trophic level is a feeding level. From the greek word trophe meaning nourishment.

Construct a Pyramid of Biomass.

There is less energy and less biomass every time you move up a trophic level in a food chain. There are normally fewer organisms in each level too.

100 flowers ---> 10 rabbits ----> 1 Fox  (-----> = eaten by)

This is not always the case as 500 fleas may be feeding on one fox so the number of organisms has increased in the next level. So we think about biomass not numbers. You can use the information to construct a pyramid of biomass to represent a food chain.

1) Each bar of a pyramid of biomass shows the mass of living material (basically their…