u8 ecology

Vocab for Unit 8: Ecology (AP Biology)

Organism

A single living individual.

Population

A group of individuals of the same species living in the same area.

Community

All the different populations interacting in an area.

Ecosystem

The community plus abiotic (non-living) factors in an area.

Biome

A large ecological region with similar climate and organisms.

Biosphere

All ecosystems on Earth, including land, water, and air.

Abiotic Factors

Non-living parts of an environment (e.g., sunlight, water, temperature).

Biotic Factors

Living parts of an environment (e.g., plants, animals, bacteria).

Trophic Level

A step in a food chain or web (e.g., producer, primary consumer).

Autotroph (Producer)

An organism that makes its own food via photosynthesis or chemosynthesis.

Heterotroph (Consumer)

An organism that eats other organisms for energy.

Food Chain

A linear flow of energy through an ecosystem.

Food Web

A complex network of interconnected food chains.

Primary Productivity

The rate at which producers convert sunlight into energy.

Gross Primary Productivity (GPP)

Total energy produced.

Net Primary Productivity (NPP)

Energy left after producers use some for respiration.

Energy Pyramid

A diagram showing energy loss at each trophic level (10% Rule: only 10% of energy moves up).

Biomass

The total mass of living organisms in a given area.

Water Cycle

The continuous movement of water through evaporation, condensation, precipitation, and runoff.

Carbon Cycle

Movement of carbon through respiration, photosynthesis, fossil fuels, and the atmosphere.

Nitrogen Cycle

Movement of nitrogen through nitrogen fixation, nitrification, and denitrification.

Phosphorus Cycle

The cycling of phosphorus between rocks, soil, water, and organisms.

Population Density

Number of individuals per unit area.

Dispersion Patterns

The way individuals are spaced in an area.

Carrying Capacity (K)

The maximum population size an environment can support.

Logistic Growth (S-Curve)

Population growth that slows as it reaches carrying capacity.

Exponential Growth (J-Curve)

Rapid population increase under ideal conditions.

Density-Dependent Factors

Factors that affect populations more as they grow (e.g., competition, predation, disease).

Density-Independent Factors

Factors that affect populations regardless of size (e.g., natural disasters, climate).

r-Selected Species

Species with short lifespan, high reproduction rate, little parental care.

K-Selected Species

Species with long lifespan, few offspring, high parental care.

Type I Survivorship Curve

High survival in early/mid-life, drops in old age (e.g., humans, elephants).

Type II Survivorship Curve

Constant mortality rate (e.g., birds, squirrels).

Type III Survivorship Curve

High mortality early, few survive to adulthood (e.g., fish, plants).

Niche

An organism’s role in its environment.

Fundamental Niche

The full range of conditions a species could use.

Realized Niche

The actual conditions a species uses due to competition.

Competitive Exclusion Principle

No two species can occupy the same niche in the same habitat.

Resource Partitioning

Species use resources differently to reduce competition.

Mutualism

A symbiotic relationship where both species benefit.

Commensalism

A symbiotic relationship where one species benefits, the other is unaffected.

Parasitism

A symbiotic relationship where one species benefits and the other is harmed.

Keystone Species

A species that has a major impact on its ecosystem.

Invasive Species

Non-native species that disrupt ecosystems.

Predation

One organism (predator) kills and eats another (prey).

Herbivory

An organism eats plants.

Ecological Succession

Natural process of ecosystem change over time.

Primary Succession

Starts on bare rock (no soil), e.g., volcanic island formation.

Secondary Succession

Happens after a disturbance (e.g., forest fire).

Biodiversity

The variety of life in an ecosystem.

Ecosystem Services

Benefits ecosystems provide.

Climate Change

Long-term changes in global temperatures and weather patterns.

Deforestation

Large-scale removal of trees, affecting ecosystems and climate.

Biomagnification

The increase in toxic substance concentration at higher trophic levels.

Eutrophication

Excess nutrients in water cause algae blooms and dead zones.

Habitat Fragmentation

The breaking up of ecosystems due to human activities.

Conservation Biology

The study of protecting and restoring biodiversity.

Ecological Footprint

The impact of human activities on the environment.