Connecting to Your World The first tools were objects such as a stone with a sharp edge. In time, people learned to reshape these objects to produce better tools. Native Americans in what is now Illinois drilled holes in mussel shells and carved lines onto the shells to make them look like small fish. The shells were likely used as lures for ice fishing. People also began to produce materials that did not exist in nature. By weaving plant fibers together, they made cloth, which is softer and dries more quickly than animal skins. Chemistry plays a key role in the production of new materials. In this section, you will learn how chemistry affects many aspects of modern life.

Key Concepts

• What impact do chemists have on materials, energy, medicine, agriculture, the environment, the study of the universe

Vocabulary

• macroscopic

• microscopic

• biotechnology

• pollutant

Reading Strategy

Monitoring Your Understanding After you read this section, identify something you learned that is important to your life and explain why it is important to you.

Guided Reading and Study Worksheet