Chapter 36

Which type of organism forms the base of a food chain?

• decomposer

• consumer

• carnivore

• omnivore

• producer

In a terrestrial ecosystem, a mouse eating a grasshopper is an example of a

• primary consumer.

• secondary consumer.

• tertiary consumer.

• quaternary consumer.

• decomposer.

What ultimately determines a terrestrial ecosystem's total energy budget?

• the amount of biomass

• the number of decomposers in the ecosystem

• the number of levels in the food chain

• the amount of sunlight

• the complexity of the food web

The primary productivity that top-level consumers such as lions and killer whales have no natural predators?

• Factors such as rainfall and temperature can influence productivity.

• Factors such as rainfall and temperature are not important in determining productivity.

• Terrestrial ecosystems are not important in terms of primary productivity.

• There are no producers in the tundra.

• all of the above

___ break down organisms and supply the soil, water, and air with chemicals in inorganic form.

• Producers

• Primary consumers

• Secondary consumers

• Tertiary consumers

• Decomposers

Which is NOT an example of a nonliving process that can play a role in the carbon cycle?

• volcanic eruptions

• using natural gas to heat your home

• cellular respiration

• forest fires

• driving a car

During the process of nitrogen fixation, ___ is converted into ___.

• ammonia; nitrogen gas

• ammonium; nitrate

• nitrate; ammonia

• nitrogen gas; ammonia

• ammonia; ammonium

Nitrogen fixation is carried out by

• animals that eat plants.

• bacteria in the roots of certain plants.

• fungi.

• bacteria in the air.

• animals that live in the soil

What are two ways in which water may reenter the atmosphere in gaseous form?

• transpiration and evaporation

• evaporation and precipitation

• condensation and precipitation

• transpiration and precipitation

• condensation and evaporation

How can humans impact chemical cycles on Earth?

• by moving nutrients from one place to another

• by burning the tropical rainforests

• by using fossil fuels

• all of the above

• none of the above