Ch. 5 Key Terms Flashcards
photosynthesis
Energy from the sun enters an ecosystem when a plant uses sunlight to make sugar molecules in a process.
producer
It is an organisms that makes its own food. It is also called autotrophs.
consumer
Organisms that get their energy by eating other organisms. It is also called heterotrophs.
decomposer
Some consumers get their food by breaking down dead organisms.
cellular respiration
The process of breaking down food to yield energy.
food chain
It is a sequence in which energy is transferred from one organism to the next as each organism eats another organisms.
food web
It show many feeding relationships that are possible in an ecosystem.
trophic level
Each step through which energy is transferred in a food chain.
carbon cycle
It is a process by which carbon is cycled between the atmosphere, land, water, and organisms.
nitrogen-fixing bacteria
The only organisms that can fix atmospheric nitrogen into chemical compounds are a few species of bacteria.
nitrogen cycle
A process in which nitrogen is cycled between the atmosphere, bacteria, and other organism.
phosphorus cycle
It is the movement of phosphorus from the environment to organisms and then back to the environment.
ecological succession
It is a gradual process of change and replacement of some or all of the species in a community.
primary succession
It is the type of of succession that occurs on a surface where no ecosystem existed before, such as on rocks or sand dunes.
secondary succession
The more common type of succession, occurs on a surface where an ecosystem has previously existed.
