Ecology (IB)

Abiotic Factors

Non-living components of an ecosystem

Ecology

Study of interactions between organisms and their environment

Interdependence

The interconnectedness of organisms and their environment

Holistic Approach

Studying systems as a whole rather than in isolated parts

Individual

Single organism in an ecosystem

Population

Group of individuals of the same species in a specific area

Community

All populations of different species in an area

Producers/Autotrophs

Organisms that make their own food.

Ecosystem

Community of organisms and their non-living environment.

Biosphere

Global sum of all ecosystems where life exists.

Biotic Factors

Living components of an ecosystem

Primary Consumers

Herbivores that eat producers

Secondary Consumers

Carnivores that eat primary consumers

Tertiary Consumers

Top predators that eat secondary consumers

Decomposers

Organisms that break down dead matter and recycle nutrients

Competition

When organisms vie for the same resources

Predation

Interaction where one organism hunts and eats another

Symbiosis

Long-term interaction between different species

Herbivory

Consumption of plants by herbivores

Climate

Long-term patterns of temperature and precipitation in an area

Soil

Upper layer of Earth’s surface where plants grow

Water

Essential liquid for life processes and ecosystem functioning

Sunlight

Primary energy source for photosynthesis

Nutrients

Chemical elements required for organism growth and survival

Topography

Physical features of Earth’s surface, like elevation and slope

Exponential Growth

Rapid increase in population size with abundant resources

Logistic Growth

Population growth that slows as it reaches carrying capacity

Carrying Capacity (K)

Maximum population size an environment can support.

10% Rule

Only 10% of energy is transferred to the next trophic level.

Food Web

Network of interconnected food chains in an ecosystem.

Food Chain

Linear sequence of organisms where each is consumed by the next.

Photosynthesis

Process by which producers convert light energy into chemical energy in glucose.

Decomposers/Saprotrophs

Organisms that break down dead organic matter to recycle nutrients.

Nitrogen Fixation

Conversion of atmospheric nitrogen into ammonia by bacteria.

Assimilation (Nitrogen Cycle)

Plants absorb nitrates from the soil and use them to build proteins.

Ammonification

Decomposition of organic nitrogen into ammonia by decomposers.

Denitrification

Conversion of nitrates back into nitrogen gas by denitrifying bacteria.

Biogeochemical Cycles

Processes that recycle nutrients through ecosystems (e.g., water, carbon, nitrogen).

Pyramid of Energy

Graphical representation showing energy available at each trophic level.

Nitrification

Conversion of ammonia into nitrate by nitrifying bacteria.