Ecology Lecture Notes

A set of flashcards covering key concepts in ecology, including definitions and relationships between living organisms and their environments.

Ecology

The scientific study of interactions between organisms and their environments, focusing on energy transfer.

Environment

Made up of biotic factors (all living organisms) and abiotic factors (nonliving parts like temperature, soil, and moisture).

Biotic Factors

All living organisms inhabiting the Earth.

Abiotic Factors

Nonliving parts of the environment, such as temperature, soil, light, moisture, and air currents.

Organism

Any unicellular or multicellular form exhibiting all characteristics of life; the lowest level of organization.

Population

A group of organisms of the same species living in the same place at the same time that interbreed and produce fertile offspring.

Community

Several interacting populations that inhabit a common environment and are interdependent.

Ecosystem

Populations in a community and the abiotic factors with which they interact.

Biosphere

Life-supporting portions of Earth composed of air, land, fresh water, and salt water; the highest level of organization.

Niche

The role a species plays in a community; its total way of life.

Habitat

The place in which an organism lives out its life.

Limiting Factor

Any biotic or abiotic factor that restricts the existence of organisms in a specific environment.

Symbiosis

Two species living together; can be commensalism, parasitism, or mutualism.

Commensalism

One species benefits while the other is neither harmed nor helped.

Parasitism

One species benefits (parasite) while the other is harmed (host).

Mutualism

A relationship beneficial to both species.

Trophic Level

Each link in a food chain representing a feeding step in the transfer of energy and matter.

Food Chain

A simple model that shows how matter and energy move through an ecosystem.

Food Web

Shows all possible feeding relationships in a community at each trophic level.

Primary Consumers

Herbivores that eat plants.

Secondary Consumers

Carnivores that prey on primary consumers.

Decomposers

Organisms that break down complex compounds of dead and decaying materials into simpler molecules.

Biological Magnification

The increase in potency of toxins as they move up the food chain.

Water Cycle

The processes of evaporation, transpiration, condensation, and precipitation.

Carbon Cycle

The processes of photosynthesis and respiration that cycle carbon and oxygen through the environment.

Nitrogen Cycle

The process of converting atmospheric nitrogen (N2) into usable forms like ammonium (NH4+).

Nitrogen Fixation

The process of converting atmospheric nitrogen (N2) into organic compounds such as amino acids.