Chapter 4 vocab Flashcards
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 producer
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
a series of steps in an ecosystem in which organisms transfer energy by eating and being eaten
food chain
network of complex interactions formed by the feeding relationships among the various organisms in an ecosystem
food web
photosynthetic algae found near the surface of the ocean
phytoplankton
each step in a food chain or food web
trophic 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
