In a food chain, the total amount of living material is depicted by

In a pond ecosystem,the pyramid of numbers is ............ .

The pyramid of energy is always ..........

Inverted pyramid of number and inverted pyramid of biomass are respectively seen in.

In which ecosystem is the pyramid of biomass inverted?

In a forest ecosystem, a pyramid of biomass is upright. If $P$ is at the highest trophic level, $Q$ is at the second trophic level, and $R$ is at the lowest trophic level, identify $P, Q,$ and $R$ from the following options.