AP Environmental Science Chapter 3 Flashcards

A complete set of vocabulary flashcards for AP Environmental Science Chapter 3: Ecosystems, What Are They and How Do They Work?

Biosphere

The region of our planet where life resides, the combination of all ecosystems on Earth

Producer

An organism that uses the energy of the Sun to produce usable forms of energy (also known as autotroph)

Photosynthesis

The process by which producers use solar energy to convert carbon dioxide and water into glucose

Cellular respiration

The process by which cells unlock the energy of chemical compounds

Consumer

An organism that is incapable of photosynthesis and must obtain its energy by consuming other organisms (also known as heterotroph)

Herbivore

A consumer that eats producers (also known as Primary consumer)

Carnivore

A consumer that eats other consumers

Secondary consumer

A carnivore that eats primary consumers

Tertiary consumer

A carnivore that eats secondary consumers

Trophic levels

The successive levels of organisms consuming one another

Food web

A complex model of how energy and matter move between trophic levels

Scavenger

An organism that consumes dead animals

Detritivore

An organism that specializes in breaking down dead tissues and waste products into smaller particles

Decomposers

The fungi and bacteria that complete the breakdown process by converting organic matter into small elements and molecules that can be recycled back into the ecosystem.

Gross Primary Productivity

The total amount of solar energy that producers in an ecosystem capture via photosynthesis over a given amount of time

Net Primary Productivity

The energy captured by producers in an ecosystem minus the energy producers respire

Biomass

The total mass of all living matter in a specific area

Standing crop

The amount of biomass present in an ecosystem at a particular time

Ecological efficiency

The proportion of consumed energy that can be passed from one trophic level to another

Trophic pyramid

A representation of the distribution of biomass, numbers, or energy among trophic levels

Biogeochemical cycle

The movements of matter within and between ecosystems

Hydrologic cycle

The movement of water through the biosphere

Transpiration

The release of water from leaves during photosynthesis

Evapotranspiration

The combined amount of evaporation and transpiration

Runoff

Water that moves across the land surface and into streams and rivers

Carbon Cycle

The movement of carbon around the biosphere

Macronutrients

Key elements that organisms need in relatively large amounts: nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur

Limiting nutrient

A nutrient required for the growth of an organism but available in a lower quantity than other nutrients

Nitrogen cycle

The movement of nitrogen around the biosphere

Nitrogen fixation

A process by which some organisms can convert nitrogen gas molecules directly into ammonia

Nitrification

The conversion of ammonia into nitrite and then into nitrate

Assimilation

The process by which producers incorporate elements into their tissues

Ammonification

The process by which fungal and bacterial decomposers break down the organic nitrogen found in dead bodies and waste products and convert it into inorganic ammonium

Denitrification

The conversion of nitrate in a series of steps into the gases nitrous oxide and, eventually, nitrogen gas, which is emitted into the atmosphere

Leaching

The transportation of dissolved molecules through the soil via groundwater

Phosphorus cycle

The movement of phosphorus (which rarely changes form) around the biosphere

Hypoxic

Low in oxygen

Sulfur cycle

The movement of sulfur around the biosphere

Disturbance

An event, caused by physical, chemical, or biological agents, resulting in changes in population size or community composition

Watershed

All land in a given landscape that drains into a particular stream, river, lake, or wetland

Resistance

A measure of how much a disturbance can affect flows of energy and matter in an ecosystem

Resilience

The rate at which an ecosystem returns to its original state after a disturbance

Restoration ecology

The study and implementation of restoring damaged ecosystems

Intermediate disturbance hypothesis

The hypothesis that ecosystems experiencing intermediate levels of disturbance are more diverse than those with high or low disturbance levels

range of tolerance

the range of abiotic conditions within which an organism or population can survive and reproduce

ocean acidification

The process by which today's oceans are becoming more acidic as a result of increased carbon dioxide concentrations in the atmosphere. Occurs as ocean water absorbs $CO_2$ from the air and forms carbonic acid. This threatens to dissolve coral reefs which would have strong impacts on ocean biodiversity.

chemosynthesis

using inorganic chemicals to make food. Ex. Bacteria around volcanic vents on ocean floor.

albedo

the proportion of the incident light or radiation that is reflected by a surface, typically that of a planet or moon.