Download Chapter 3 Flash Cards

Chapter 3 Vocabulary Terms
Ecology
Biosphere
Species
Scientific study of interactions among organisms and between
organisms and their environment.
The part of Earth in which life exists including land, water, and air or
atmosphere; it extends 8 km above surface and up to 11 km below
earth's surface.
A group of organisms so similar to one another that they can breed
and produce fertile offspring.
Population
Groups of individuals that belong to the same species and live in
the same area.
Community
Assemblages of different populations that live together in a defined
area.
Ecosystem
Biome
Collection of all the organisms that live in a particular place,
together with their nonliving environment, or physical environment.
A group of ecosystems that have the same climate and dominant
communities; highest level of organisms that ecologists study.
Autotroph
An organism that can capture energy from sunlight or chemicals
and use it to produce its own food from inorganic compounds; also
called a producer.
Producer
An organism that can capture energy from sunlight or chemicals
and use it to produce food from inorganic compounds; also called
an autotroph.
Photosynthesis
The process by which plants and some other organisms use light
energy to convert water and carbon dioxide into oxygen and highenergy carbohydrates such as sugars and starches.
The process by which some organisms, such as certain bacteria,
Chemosynthesis use chemical energy to produce carbohydrates; usually occurs
when no light is available.
Heterotroph
An organism that obtains energy from the foods it consumes; also
called a consumer.
Consumer
An organism that relies on other organisms for its energy and food
supply; also called a heterotroph.
Herbivore
An organism that obtains energy by eating only plants.
Carnivore
An organism that obtain their energy from eating other animals.
Omnivore
An organism that obtains energy by eating both plants and animals
Detritivore
A consumer (mites, earthworms, snails and crabs) that feeds on
dead plants, dead animals, and other dead matter, collectively
known as detritus.
Decomposer
An organism that breaks down the wastes or remains of other
organisms such as bacteria and fungi.
Food chain
A series of steps in which organisms transfer energy by eating and
being eaten.
Food web
A community of organisms where there are several interrelated food
chains.
Trophic level
Step in the movement of energy through an ecosystem; an
organism's feeding status in an ecosystem.
Ecological
pyramid
A diagram that shows the relative amounts of energy or matter
within each trophic level in a food chain or food web.
Biomass
The total amount of living tissue within a given trophic level .
Biogeochemical
cycle
The 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.
Evaporation
The process by which water changes from liquid form to an
atmospheric gas.
Transpiration
The emission of water vapor from the leaves of plants.
Nutrient
All of the chemical substances that an organism needs to sustain
life.
Nitrogen fixation The process by which certain bacteria convert nitrogen gas to
ammonia.
Denitrification
The process in which fixed nitrogen compounds are converted back
into nitrogen gas and returned to the atmosphere.
Primary
productivity
The rate at which organic matter is created by producers in an
ecosystem
Limiting nutrient
A single nutrient that either is scarce or cycles very slowly, limiting
the growth of organisms in an ecosystem.
Algal bloom
An immediate increase in the amount of algae and other producers
that result from a large input of a limiting nutrient.