Unit 2: Ecology Flashcards
biosphere
the part of Earth where life exists; includes all of the living organisms on Earth
ecosystem
a community of organisms and their abiotic environment
population
a group of organisms of the same species that live in a specific geographical area
habitat
the place where an organism usually lives
biotic factor
an environmental factor that is associated with or results from the activitiesof living organisms
abiotic factor
an environmental factor that is not associated with the activities of living organisms
niche
the unique position occupied by a species, both in terms of its function within an ecological community
producer
an organism that can makeorganic molecules; a photosynthetic or chemosynthetic autotroph that serves as the basic food source in an ecosystem
biomass
plant material, manure, or any other organic matter that is used as an energy source
consumer
an organism that eats other organisms or organic matter instead of producing its own nutrients or obtaining nutrients from inorganic sources
herbivore
an organism that eats only plants
carnivore
an organism that eats only animals
omnivore
an organism eats both plants and animals
decomposer
an organism that feeds by breaking down organic matter from dead organisms. returns nutrients
trophic level
one of the steps in a food chain or food pyramid; examples include producers and primary, secondary, and tertiary consumers
detritivore
organisms that feed on dead animal/plant remains. Ex) scavenger
chemosynthesis
process by which inorganic molecules are used to create organic molecules. Performed by autotrophs in many deep sea communities
biomagnification
increasing concentrations of a chemical in organisms at higher trophic levels due to reduced biomass
food chain
the pathway of energy transfer through various stages as a result of teh feeding patterns of a series of organisms
food web
a diagram that shows the feeding relationships between organisms in an ecosytem
population density
the number of individuals of teh same species that live in a given unit of area
geographic distribution/dispersion
in ecology, the pattern of distribution of organisms in a population (uniform, random, clumped)
exponential growth
a model of population growth with a constant and unlimited growth rate. Occurs when unlimited resources are present in the population
limiting factor
an environmental factor that prevents an organism or population from reaching its full potential of distribution or activity (density independent and dependent)
logistic growth
a model of population growth in which population growth rate slows due to limiting factors/lack of resources. Often shows a carrying capacity
carrying capacity
the largest population that an environment can support at any given time. Represented by “K” on a graph
