Ch. 3 Flashcards
Part of Earth in which life exists including land, water, and air or atmosphere
Biosphere
A group of similar organisms that can breed and produce fertile offspring
Species
Group of individuals of the same species that live in the same area
Population
Assemblage of different populations that live together in a defined area
Community
Scientific study of interactions among organisms and between organisms and their environment
Ecology
All the organisms that live in a place, together with their non living environment
Ecosystem
A group of ecosystems that share similar climates and typical organisms
Biome
Any living part of the environment with which an organism might interact
Biotic factor
Physical, or non living, factor that shapes an ecosystem
Abiotic factor
Organism that is able to capture energy from sunlight or chemicals and use it to produce its own food from inorganic compounds; also called a producer
Autotroph
First producer of energy-rich compounds that are later used by other organisms
Primary producers
Process used by plants and other autotrophs to capture light energy and use it to power chemical reactions that convert carbon dioxide and water into oxygen and energy-rich carbohydrates such as sugars and starches
Photosynthesis
Process in which chemical energy is used to produce carbohydrates
Chemosynthesis
Organism that obtains food by consuming other living things; also called a consumer
Heterotroph
Organism that relies on other organisms for its energy and food supply; also called heterotroph
Consumer
Organism that obtains energy by eating animals
Carnivore
Organism that obtains energy by eating only plants
Herbivore
Animal that consumes the carcasses of other animals
Scavenger
Organism that obtains energy by eating both plants and animals
Omnivore
Organism that breaks down and obtains energy from dead organic matter
Decomposer
Organism that feeds on plant and animal remains and other dead matter
Detritivore
Series of steps in an ecosystem in which organisms transfer energy by eating and being eaten
Food chain
Photosynthetic algae found near the surface of the ocean
Phytoplankton
Network of complex interactions formed by the feeding relationships among the various organisms in an ecosystem
Food web
Small free-floating animals that form part of plankton
Zooplankton
Each step in a food chain or food web
Tropic level
Illustration of the relative amounts of energy or matter contained within each trophic level in a given food chain or food web
Ecological pyramid
Total amount of living tissue within a given trophic level
Biomass
Process in which elements, chemical compounds, and other forms of matter are passed from one organism to another and from one part of the biosphere to another
Biogeochemical cycle
Chemical substance that an organism needs to sustain life
Nutrient
Process of converting nitrogen gas into nitrogen compounds that plants can absorb and use
Nitrogen fixation
Process by which bacteria convert nitrates into nitrogen gas
Denitrification
Single essential nutrient that limits productivity in an ecosystem
Limiting nutrient
