lesson 24 study guide

Question 1

What are the main causes of current species extinctions?

Answer 1

Habitat loss
pollution
overuse
invasive species
climate change
small populations.

Question 2

How does human population growth threaten ecosystems?

Answer 2

More people = more land, food, and water used = faster habitat and species loss.

Question 3

How does high resource use harm the biosphere?

Answer 3

Depletes water, soil, and species; drives pollution and global decline.

Question 4

Example of human impact via pollution?

Answer 4

DDT thinned bird eggs; plastics harm marine life; nitrogen runoff fuels dead zones.

Question 5

Example of human-caused resource depletion?

Answer 5

Overfishing, deforestation, groundwater drain, and habitat mining.

Question 6

How do CO₂ and CH₄ affect climate?

Answer 6

Trap heat in the atmosphere, raising global temperatures.

Question 7

Ecosystem effects of climate change?

Answer 7

Shifts species ranges, collapses food webs, worsens storms and droughts.

Question 8

Human health risks from climate change?

Answer 8

More disease, crop loss, heatwaves, air pollution, and storm damage.

Question 9

How do r-selected crops reduce biodiversity?

Answer 9

Monocultures outcompete diverse species; depend on chemicals and land.

Question 10

How does high disturbance lower biodiversity?

Answer 10

Frequent disruption prevents stable ecosystems and favors invasive species.

Question 11

How does climate change link to human health and biodiversity loss?

Answer 11

It destroys ecosystems and services we rely on—like clean air and water.