Human activities affect ecosystems. These grade level performance standards are listed developmentally. However, each school is uniquely organized. Disease in organisms results from a failure in structures and functions or damage by infection. All organisms including plants and animals are classified by their characteristics.
All organisms depend on each other.
Regulation and Behavior Behavior is one kind of response an organism can make to an internal or environmental condition. An ecosystem is composed of all populations of organisms living together and physical factors with which they interact. Populations of organisms can be categorized as producers and consumers by the function they serve in the ecosystem. These grade level performance standards are listed developmentally. However, each school is uniquely organized.