AP Environmental Science & Ecology

Question 1

What is the primary driving force behind the water cycle?

Accepted Answer

Solar energy

Answer

Solar energy drives evaporation, the process that initiates the water cycle by converting liquid water into vapor.

Question 2

Which biogeochemical cycle is most directly disrupted by burning fossil fuels?

Accepted Answer

Carbon cycle

Answer

Burning fossil fuels releases stored carbon as CO2 into the atmosphere, directly disrupting the carbon cycle's natural balance.

Question 3

In a food web, which organisms occupy the highest trophic level?

Accepted Answer

Tertiary consumers

Answer

Tertiary consumers eat secondary consumers and receive energy that has passed through all lower trophic levels, placing them at the apex.

Question 4

Which of the following best describes a keystone species?

Accepted Answer

A species with a disproportionately large impact on its ecosystem

Answer

A keystone species has effects on ecosystem structure far greater than expected from its abundance, often controlling community composition.

Question 5

What process converts atmospheric nitrogen gas (N2) into forms that plants can absorb?

Accepted Answer

Nitrogen fixation

Answer

Nitrogen fixation, performed by bacteria such as Rhizobium, converts N2 into ammonia (NH3) that plants can take up through their roots.

AP - Advanced Placement Test Practice Test