Ch 5. Key Terms Flashcards
Photosynthesis
The process by which plants, algae, and some bacteria use sunlight, carbon dioxide, and water to produce carbohydrates and oxygen.
Producer
An organism that can make organic molecules from inorganic molecules; a photosynthetic or chemosynthetic autotroph that serves as the basic food source in an ecosystem.
Consumer
An organism that eats other organisms or organic matter instead of producing its own nutrients or obtaining nutrients from inorganic sources.
Decomposer
An organism that feeds by breaking down down organic matter from dead organisms. Examples include bacteria and fungi.
Cellular Respiration
The process by which cells produce energy from carbohydrates; atmospheric oxygen combines with glucose to form water and carbon dioxide.
Food Chain
The pathway of energy transfer through various stages as a result of the feeding patterns of a series of organisms.
Food Web
A diagram that shows the feeding relationships between organisms in an ecosystem.
Trophic Level
One of the steps in a food chain or food pyramid; examples include producers and primary, secondary, and tertiary consumers.
Carbon Cycle
The movement of carbon from the nonliving environment into living things and back.
Nitrogen-fixing Bacteria
Bacteria that convert atmospheric nitrogen into ammonia.
Nitrogen Cycle
The process in which nitrogen circulates among the air, soil, water, plants, and animals in an ecosystem.
Phosphorus Cycle
The cyclic movement of phosphorus in different chemical forms from the environment to organisms and then back to the environment.
Ecological Succession
A gradual process of change and replacement in a community.
Primary Succession
Succession that begins in an area that previously did not support life.
Secondary Succession
The process by which one community replaces another community that has been partially or totally destroyed.
