2. I. A view from space reveals that the Earth and its natural resources are limited.

4. A. Environmental scientist study (1.) How the natural world works. (2.) How humans and the environment affect each other. (3.) Issues that are important to our world and its future.

5. B. Includes (1.) All living and nonliving “things” with which organisms interact. (a.) Things can be continents, oceans, animals, plants, remote areas, buildings,

6. C. Humans and the environment 1.Humans interact with the environment and rely on a healthy functioning planet for everything they need. 2. Humans are part of the natural world and how they interact with it matters a great deal. 3.Human improvements have often harmed the natural systems that sustain them, destroyed habitats and polluted the water and atmosphere.

7. 1.Environmental science is an interdisciplinary field that pursues knowledge about the workings of the environment and our interactions with it. 2. Environmentalism is a social movement dedicated to protecting the natural world from undesirable changes brought about by human actions. Environmentalists protesting the use of nuclear power.

9. A. In the last several hundred years, both human populations and resource consumption have increased dramatically. Did You Know? The human population increases by about 200,000 people every day.

10. B. Natural Resources 1. Are limited materials and energy sources found in nature, that humans need to survive.

11. B. Natural Resources 2. There are two types (a.) Renewable which are naturally replenished over short periods. (b.) Nonrenewable which are naturally formed more slowly than they are used. - Once they are used up that are gone forever.

12. 1. Can be quantified by using the concept of the “ecological footprint.” (a.) Expresses the environmental effects of an individual or population in terms of the total amount of land and water required to: - Provide raw materials the individual or population consumes. - Dispose of or recycle the waste that is produced.

13. D. Tragedy of the commons 1. Increased resource use can cause the “tragedy of commons.” (a.) According to Garrett Harden, unless resources are regulated, we will eventually be left with nothing. A commercial fishing boat in Alaska brings in a catch of sockeye salmon