AP Biology Chapter 42: Ecosystems and Energy

These flashcards cover key concepts from Chapter 42 of AP Biology about ecosystems and energy.

What is an ecosystem?

The sum of all the organisms living in a given area and the abiotic factors with which they interact.

What are the two key emergent properties of an ecosystem?

Energy flow and chemical cycling.

How does energy primarily enter ecosystems?

As sunlight.

What is the process by which autotrophs convert light energy to chemical energy?

Photosynthesis.

What is chemical cycling in ecosystems?

The process by which elements like carbon and nitrogen are passed between biotic and abiotic components.

What does the first law of thermodynamics state?

Energy cannot be created or destroyed, only transferred or transformed.

What is the second law of thermodynamics in relation to ecosystems?

Every exchange of energy increases the universe's entropy.

What are primary producers?

The trophic level that ultimately supports all others, consisting of autotrophs.

What role do primary consumers play in an ecosystem?

They eat primary producers.

What are decomposers?

Organisms that absorb nutrients from nonliving organic material and convert them to inorganic forms.

What is primary production?

The amount of light energy converted to chemical energy by autotrophs during a given time period.

What is gross primary production (GPP)?

The amount of energy from light converted to the chemical energy of organic molecules per unit time.

What does net primary production (NPP) represent?

The storage of chemical energy that will be available to consumers in the ecosystem.

What typically limits primary production in aquatic ecosystems?

Nutrients, particularly nitrogen and phosphorus.

What is eutrophication?

A process in which nutrient concentrations become highly concentrated in a body of water, leading to increased growth of algae.

What are two key factors controlling primary production in terrestrial ecosystems?

Temperature and moisture.

How can climate change affect NPP in ecosystems?

By altering temperature and precipitation patterns.

What percentage of energy is typically transferred between trophic levels?

About 10%.

What is biological augmentation?

The use of organisms to add essential materials to a degraded ecosystem.

What is bioremediation?

The use of organisms to detoxify and restore polluted ecosystems.