The Living World: Ecosystems
The Living World: Biodiversity
Populations
Earth Systems and Resources
Water Use
100

This process describes how plants convert sunlight into chemical energy.

Photosynthesis

100

This term refers to the variety of life in a particular area, including species, genetic, and ecosystem diversity.

Biodiversity

100

This term refers to a group of individuals of the same species living in the same area.

Population

100

This sphere of the Earth includes all living organisms.

Biosphere

100

This sector uses the largest percentage of freshwater globally, primarily for irrigation.

Agriculture

200

These organisms break down dead organic matter and recycle nutrients back into the ecosystem.

Decomposers

200

This type of species is naturally found in a specific area and nowhere else in the world.

Endemic species

200

This measures the number of individuals per unit area.

Population density

200

This layer of the atmosphere is where weather occurs.

Troposphere

200

This type of water is found underground in soil and rock formations.

Groundwater

300

This trophic level consists of organisms that make their own food, typically through photosynthesis.

Primary producers

300

This biome is characterized by extremely low precipitation and sparse vegetation.

Desert

300

This growth model shows rapid population increase when resources are unlimited.

Exponential growth

300

This process involves the breakdown of rock into smaller pieces without changing its chemical composition.

Mechanical (physical) weathering

300

This irrigation method delivers water directly to plant roots, minimizing evaporation.

Drip Irrigation

400

This law states that about 90% of energy is lost from one trophic level to the next.

The 10% Rule

400

This ecosystem has the highest biodiversity on Earth and is located near the equator.

Tropical rainforest

400

This type of growth occurs when a population slows as it approaches carrying capacity.

Logistic growth

400

This soil horizon is rich in organic matter and is typically the most fertile layer.

O horizon (or A horizon if specified as topsoil)

400

This environmental issue occurs when coastal aquifers are overdrawn, allowing seawater to enter.

Saltwater intrusion

500

This term describes a species that has a disproportionately large effect on its environment relative to its abundance.

Keystone species

500

This concept measures the number of different species in a given area.

Species richness

500

These factors limit population growth regardless of population size, such as hurricanes or wildfires.

Density-independent factors

500

This type of plate boundary occurs when two plates move away from each other.

Divergent boundary

500

This agricultural problem occurs when irrigation without proper drainage raises the water table and harms crops.

Waterlogging

600

This type of succession occurs in an area where soil already exists after a disturbance.

Secondary succession

600

This term describes the variety of genes within a particular species or population.

Genetic diversity

600

This term describes the average number of children born to a woman over her lifetime.

Total fertility rate (TFR)

600

This process moves soil and sediment from one place to another, often by wind or water.

Erosion

600

This concept explains how individuals acting in their own self-interest can deplete a shared resource.

Tragedy of the Commons

700

This is the maximum population size of a species that an environment can sustain indefinitely.

Carrying capacity

700

This hypothesis suggests that larger habitats closer to the mainland will have greater species diversity due to higher immigration rates.

Island biogeography theory

700

This type of survivorship curve shows high mortality early in life, common in species like fish or insects.

Type III survivorship curve

700

This phenomenon occurs when water infiltrates the ground and replenishes underground aquifers.

Groundwater recharge

700

This practice involves catching fish faster than they can reproduce, leading to population declines.

Overfishing

800

This symbiotic relationship benefits one organism while harming the other.

Parasitism

800

This phenomenon occurs when wildlife areas are split into isolated patches, reducing species survival and genetic exchange.

Habitat fragmentation

800

This term refers to the maximum population size an environment can sustain over time.

Carrying capacity

800

This layer of the atmosphere contains the ozone layer and absorbs harmful UV radiation.

Stratopshere

800

This fishing method unintentionally captures non-target species such as dolphins or sea turtles.

Bycatch

900

This cycle has its largest reservoir in the atmosphere.

The Nitrogen Cycle

900

This category of ecosystem services includes tangible products like food, timber, and fresh water.

Provisioning services

900

This phenomenon occurs when a population exceeds carrying capacity and experiences a sharp decline.

Overshoot and die-off

900

This process describes the downward movement of water through soil layers due to gravity.

Percolation
900

This method of fishing uses large nets dragged along the ocean floor, often damaging benthic ecosystems.

Bottom trawling

1000

This principle states that two species competing for the same limiting resource cannot coexist at constant population values.

Competitive exclusion principle

1000

Forests provide this regulating service by absorbing carbon dioxide from the atmosphere.

Carbon sequestration

1000

This demographic transition stage is characterized by low birth rates, low death rates, and stable or declining population.

Stage 4 (or Stage 5 if specified) of the demographic transition model

1000

This climate pattern is characterized by weakened trade winds, a shift of warm surface water toward the eastern Pacific, reduced upwelling off the west coast of South America, and typically leads to increased rainfall in the southern United States.

El NiƱo

1000

This concept describes harvesting a renewable resource at a rate that allows it to replenish indefinitely.

Maximum sustainable yield

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