RECOGNIZE THE ENVIRONMENT AS A SYSTEM OF INTERDEPENDENT COMPONENTS AFFECTED BY HUMAN ACTIVITY AND NATURAL PHENOMENA.

A STUDENT SHOULD KNOW THAT:

A. PERSONAL AND SOCIETAL ACTIVITIES IMPACT THE ENVIRONMENT.

1. Natural systems are affected by human activity.
2. Human activities cause lasting effects in the environment upon which all life depends.
3. Some human activities have led to extinction of numerous species of plants and animals, primarily through habitat destruction.

B. HUMAN PRACTICE AFFECTS THE USE AND MANAGEMENT OF NATURAL RESOURCES.

1. Through increased awareness of ecological interactions, humans have attempted to prevent continued disruption of the environment and to counteract the results of many of their past negative practices.

C. INDIVIDUALS AND GROUPS MAY HAVE DIFFERING POINTS OF VIEW ON ENVIRONMENTAL
     ISSUES.

D. IN AN ECOSYSTEM, LIVING COMMUNITIES AND THEIR PHYSICAL ENVIRONMENT FUNCTION 
     TOGETHER AS AN INTERDEPENDENT AND RELATIVELY STABLE SYSTEM.

1. Living organisms interact with each other and their environment to form an ecosystem.
2. An ecosystem includes relationships that cycle and recycle materials between organisms and their environment.
3. An ecosystem must contain a constant supply of energy which is available to all organisms within the ecosystem. The energy must flow from organism to organism through a food web.
4. Ecosystems are systems that are constantly changing resulting in changes to the make-up of the community.
   1. Lake succession, e.g., lakes naturally fill in with silt over time eventually resulting in a forest.
   2. Old field succession, e.g., a series of changes that goes from grass to forest.

TO UNDERSTAND THE CONCEPTS OUTLINED ABOVE, A STUDENT SHOULD BE ABLE TO:

• Explain how organisms are affected by different components and changes in an ecosystem.
• Predict the effect of a particular pollutant on a given component of an ecosystem.
• Infer possible causes of environmental damage.