AP Environmental Science Practice Questions, Examples, and FRQ Samples

In a food chain, approximately what percentage of energy is transferred from one trophic level to the next?

• A1%
• B10%
• C50%
• D90%

Which process adds CO₂ to the atmosphere?

• APhotosynthesis
• BCellular respiration
• CChemosynthesis
• DTranspiration

A country has high birth rates and high death rates, with little population growth. This describes which stage of the demographic transition?

• AStage 1 (pre-industrial)
• BStage 2 (early industrial)
• CStage 3 (late industrial)
• DStage 4 (post-industrial)

Which of the following is an example of sustainable agricultural practice?

• AMonoculture planting of corn year after year
• BUsing synthetic fertilizers without soil testing
• CCrop rotation with legumes to restore soil nitrogen
• DTilling the soil deeply each season

A country plans to replace a coal plant with either a wind farm or a nuclear plant to reduce CO₂ emissions.

Which statement correctly describes a trade-off of the two options?

• ABoth produce CO₂ during operation, but the wind farm emits less.
• BWind requires more land but has lower fuel risk; nuclear has high energy density but long-lived radioactive waste.
• CNuclear produces more greenhouse gases than wind because of uranium mining.
• DWind is more reliable because it is always available.

Which condition most promotes the formation of photochemical smog?

• ACool, cloudy days with little traffic
• BWarm, sunny days with high NOₓ and VOC concentrations
• CCold winter air with wood-burning stoves
• DNighttime calm over mountainous terrain

Runoff from fertilized fields enters a lake. Algal blooms form, and months later, fish in the lake die.

Which chain of events best explains the fish kill?

• AFertilizer directly poisons the fish.
• BAlgae block sunlight, starving the fish of vitamin D.
• CNutrients cause algal blooms; decomposition of dead algae consumes dissolved O₂, asphyxiating fish.
• DFertilizer raises pH sharply, preventing fish from absorbing oxygen.

Which gas contributes the most to anthropogenic global warming by total radiative forcing, given current atmospheric concentrations?

• AMethane (CH₄)
• BCarbon dioxide (CO₂)
• CNitrous oxide (N₂O)
• DWater vapor (H₂O)

Which of the following is an example of a regulating ecosystem service?

• ATimber harvest
• BPollination of crops by bees
• CRecreational fishing
• DCultural significance of sacred forests

A stream's dissolved oxygen (DO) measurements decrease from 9 mg/L upstream of a wastewater discharge point to 3 mg/L 2 km downstream, then rise back to 8 mg/L by 6 km downstream.

Which explanation best fits the data?

• AThe wastewater caused a pH drop that damaged oxygen-sensing equipment.
• BDecomposition of organic matter in wastewater consumed DO; the stream later recovered via reaeration and dilution.
• CFish downstream died and stopped consuming oxygen.
• DAlgae at the discharge point blocked oxygen from entering the stream.