AP Environmental Science Unit 8: Aquatic and Terrestrial Pollution practice questions

Question 1

Regulators can slap a permit on one factory's discharge pipe but struggle to control fertilizer washing off a thousand farms. What makes the pipe a 'point source' and the easier one to regulate?

Accepted Answer

A point source is a single, identifiable origin of pollution. One pipe or smokestack can be pinpointed, permitted, and regulated.

Answer

Any pollution source that can be measured with instruments

Answer

Pollution that travels a long distance before affecting ecosystems

Answer

A diffused source spread across a wide geographic area

Question 2

Urban stormwater runoff carrying fertilizers into a river — point source or nonpoint source? Why?

Accepted Answer

Nonpoint source — pollution is diffused widely across a large area. There's no single identifiable origin to pinpoint.

Answer

Point source, because the pollution enters the river at a specific location

Answer

Point source, because it can be traced back to human activity

Answer

Neither — stormwater is a natural process and not regulated as pollution

Question 3

What does an oxygen sag curve show, and what causes the 'sag'?

Accepted Answer

A plot of dissolved oxygen versus distance from a pollution source. The sag is where bacteria decomposing waste consume oxygen, dropping DO downstream.

Answer

A graph of algae population vs. nutrient concentration in a lake

Answer

A curve showing how thermal pollution reduces oxygen near a power plant outflow

Answer

A plot of pH change versus distance from an acid mine drainage site

Question 4

Elemental mercury enters a river. What transformation makes it especially dangerous to aquatic food webs?

Accepted Answer

Bacteria convert elemental mercury into methylmercury, a toxic, fat-soluble form. Methylmercury bioaccumulates up the food web.

Answer

Sunlight oxidizes mercury into mercuric chloride, which dissolves in water and poisons fish directly

Answer

Mercury binds to sediment particles, which fish ingest when feeding on the bottom

Answer

Algae absorb elemental mercury and convert it to a water-soluble form that moves up the food chain

Question 5

What are endocrine disruptors?

Accepted Answer

Chemicals that disrupt the endocrine system by blocking or mimicking hormones. They throw off animals' hormone signaling.

Answer

Chemicals that destroy the ozone layer and increase UV radiation reaching Earth

Answer

Pathogens that infect endocrine glands and reduce hormone production

Answer

Heavy metals that accumulate in the liver and disrupt enzyme activity

Question 6

DDT enters a river ecosystem. Which ecological effects are linked to endocrine disruption in affected species?

Accepted Answer

Birth defects, developmental disorders, and gender imbalances in fish and other species.

Answer

Immediate mass mortality of fish due to direct toxicity at all trophic levels

Answer

Reduction in photosynthesis rates in aquatic plants, collapsing the food web

Answer

Increased mutation rates in bacteria, leading to antibiotic resistance in the ecosystem

Question 7

A coastal town drains its wetland to build housing, and the next big storm leaves the new neighborhood underwater. Which wetland service did they destroy?

Accepted Answer

Flood protection — wetlands soak up and release storm water like a sponge. That buffers nearby land from surge and flooding.

Answer

Carbon sequestration, since draining the wetland released stored carbon

Answer

Oxygen production, since the wetland plants were the town's main air supply

Answer

Crop pollination, since the wetland supported the region's pollinators

Question 8

A coastal mangrove forest is cleared for shrimp farming. Identify two environmental consequences.

Accepted Answer

Lost storm-surge protection and lost coastal nursery habitat for fish and marine species. Coastal erosion rises and fish populations fall.

Answer

Increased freshwater availability and improved water quality due to removal of salt-tolerant vegetation

Answer

Reduced eutrophication because mangroves were trapping excess nutrients in their roots

Answer

Decreased atmospheric CO2 absorption by the ocean because surface reflectivity increases

AP Environmental Science — Unit 8: Aquatic and Terrestrial Pollution

What AP Environmental Science Unit 8 covers

AP Environmental Science Unit 8 practice questions

Key terms in Unit 8

Drill all of Unit 8 with spaced repetition