For a grassland ecosystem, the pyramid of number is upright as the number of organisms decreases at it moves to a higher trophic level.

Pyramid of energy doesn’t vary with the tophic level, but it always remains upright. It actually reflects the law of thermodynamics, which indicates that loss of energy at each trophic level will transfer to the next trophic level.

Carnivores have a high assimilation efficiency, but their production efficiency is lower than the herbivore.

Ecosystems are of many types, out of which four most common ecosystems are: natural, terrestrial, aquatic, and artificial. Forest, grassland, and desert are examples of terrestrial ecosystem.

Aquatic ecosystem has been broadly divided into fresh and marine water ecosystem. In fresh water lotic means running water, i.e., river while lentic ecosystem consists of lake and pond.