Matter and Energy in Ecosystems

As energy moves through trophic levels, each level receives less because energy is

• used in life processes and lost as heat.

• added to the system.

• consumed by carnivores.

• incorporated into biomass.

Most of the energy in ecosystems is provided by

• omnivores

• producers

• carnivores

• keystone species

Biomass is

• the unused excrement in a given area

• the amount of herbivores in an area

• the mass of all living things on Earth

• the mass of the living and dead organisms in a given area

The ultimate source of almost all the energy used by producers is

• decomposing matter

• recycled nutrients

• the sun

• water

Which of the following can be both a primary and secondary consumer?

• carnivores

• omnivores

• herbivores

• producers

A pyramid of numbers shows

• the number of organisms in an ecosystem

• the amount of biomass in an ecosystem

• a chain of feeding relationships

• a network of feeding relationships

Lions eat only meat. What are lions?

• omnivores

• herbivores

• carnivores

• autotrophs

The smaller toothed whale feeds mostly at the

• third and fourth trophic level

• the fourth trophic level only

• the second trophic level

• the first and second trophic level

How much energy is available to the secondary consumers?

• all of the energy in the producers and primary consumers

• all of the energy in the producers minus the energy in the primary in consumers

• 10% of the energy in the primary consumers

• 90 percent of the energy in the primary consumers

When a rabbit eats clover, it incorporates the clover into its own

• biomass

• community

• niche

• biome