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. Producers are also called autotrophs, or self-feeders
Consumer
organisms that get their energy by eating other organisms. Consumers are also called heterotrophs, or other-feeders.
Decomposer
Consumers get their food by breaking down organic matter from dead organisms.
Cellular Respiration
The process of breaking down carbohydrates to yield energy
Food Chain
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
a process by which carbon is cycled between the atmosphere, land, water, and organisms.
Nitrogen-Fixing Bacteria
can fix atmospheric nitrogen into a useful form called ammonia
Nitrogen Cycle
a process in which nitrogen is cycled between the atmosphere, soil, and organisms
Phosphorus Cycle
the movement of phosphorus from the environment to organisms and then back to the environment. This cycle does not include the atmosphere because phosphorus rarely occurs as a gas
Ecological Succession
a gradual process of change and replacement of some or all of the species in a community
Primary Succession
Succession that occurs 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.
