Unit 8 : Ecology Flashcards
Ecology
The study of interactions between organisms and their environment
Population
A group of individuals of the same species living in the same area
Community
All the different populations that live together in an area
Ecosystem
A community of organisms and their abiotic environment
Biome
A large area characterized by specific climate and organisms
Biosphere
The global ecosystem; all life on Earth and the environments they inhabit
Biotic factor
A living component of the environment (e.g., plants, animals)
Abiotic factor
A nonliving component of the environment (e.g., sunlight, water, temperature)
Trophic level
A step in a food chain or food web
Producer (autotroph)
An organism that produces its own food from sunlight or chemicals
Consumer (heterotroph)
An organism that obtains energy by consuming other organisms
Decomposer
An organism that breaks down dead or decaying organisms
Food chain
A linear sequence of organisms through which energy is transferred
Food web
A network of interconnected food chains showing energy flow in an ecosystem
Energy pyramid
A diagram that shows the energy transfer between trophic levels; about 10% of energy is passed on
Carrying capacity
The maximum population size that an environment can support
Limiting factor
An environmental factor that restricts population growth
Density-dependent factor
A factor whose effect on population size increases with population density (e.g., disease, competition)
Density-independent factor
A factor that affects population size regardless of population density (e.g., weather, natural disasters)
Exponential growth
Growth pattern in which a population grows rapidly under ideal conditions
Logistic growth
Growth pattern that levels off as the population reaches carrying capacity
Niche
An organism’s role in its ecosystem, including habitat, food source, and interactions
Competition
When organisms attempt to use the same resource in the same place and time
Predation
An interaction in which one organism kills and eats another
Symbiosis
A close ecological relationship between two species
Mutualism
A symbiotic relationship in which both species benefit
Commensalism
A symbiotic relationship where one organism benefits and the other is unaffected
Parasitism
A symbiotic relationship in which one organism benefits at the expense of the other
Succession
The series of predictable changes that occur in a community over time
Biodiversity
The variety of life in an area; higher biodiversity often indicates a healthier ecosystem
Invasive species
A non-native species that spreads widely and causes harm to the environment, economy, or human health
Keystone species
A species that has a disproportionately large effect on its ecosystem
Ecosystem services
The benefits humans receive from ecosystems (e.g., clean water, pollination, climate regulation)
