Question

why pyramids are used to show food chain of of biomass

Answer 1

 a pyramid of biomass is a better diagram to use.A pyramid of biomass shows the total mass of organisms at each stage of a food chain. In general, all producers have a higher biomass than the primary consumer, so a pyramid will always be produced. The total energy (and biomass) present at a lower tier of the pyramid, must be greater than the higher tiers in order to support the energy requirements of the subsequent organisms.

Answer 2

the pyramid shows the total biomass of organism at each stage.
i.e. the total biomass in -producers >that in primary consumers>secondary consumers..