Food Web and Pyramids

What is a trophic level in a food pyramid?

• A measure of an organism's size

• The number of organisms in an ecosystem

• A number that signifies an organism's position on a food chain or pyramid

What does the '10% Rule' describe in the context of a food chain?

• Only 10% of organisms in a trophic level survive to reproduce.

• Only about 10% of the chemical energy consumed by an organism is passed on to the next trophic level.

• 10% of all species in an ecosystem are decomposers.

Why does a food pyramid typically have a pyramid shape instead of a column shape?

• Because there are more predators than producers in most ecosystems.

• Because energy is lost at each successive trophic level, requiring a larger biomass at lower levels to support higher ones.

• To represent the different types of habitats found within an ecosystem.

What is the primary role of decomposers in an ecosystem's food pyramid?

• They are apex predators that control the populations of other consumers.

• They convert sunlight into chemical energy, forming the base of the pyramid.

• They break down organic waste and dead tissue, returning essential nutrients to the soil.