“Ch. 5 Key Terms" Flashcards
photosynthesis
Energy from the sun enters an ecosystem when organisms use sunlight to make sugar in a process
producer
An organism that makes its own food
consumer
Organisms that get their energy by eating other organisms
decomposer
Consumers that get their food by breaking down organic matter from dead organisms
cellular respiration
The process of breaking down carbohydrates to yield energy
food chain
Is the path in which energy is transferred from one organism to the next as each organism eats another organism.
food web
Includes more organisms and shows the feeding relationships between organisms that are possible in an ecosystem.
trophic level
Each step through which energy is transferred in a food chain
carbon cycle
Is a process by which carbon is cycled between the atmosphere, land, water, and organisms.
nitrogen-fixing bacteria
It must be altered, or fixed, before organisms can use it. Only a few species of bacteria,
nitrogen cycle
A process in which nitrogen is cycled between the atmosphere, soil, and organisms.
phosphorus cycle
is the movement of phosphorus from the environment to organisms and then back to the environment.
ecological succession
Is a gradual process of change and replacement of some or all of the species in a community.
primary succession
Succession can occur in areas that previously did not support life, such as on rocks or sand dunes.
secondary succession
Occurs in areas where an ecosystem has previously existed. For example, ecosystems that have been disturbed or disrupted by humans or animals, or by natural processes such as storms, floods,and earthquakes can regrow through secondary succession
