Answer the following questions. You will receive immediate feedback when you select your answer or when you click on the green check mark (). When you are finished, click the How Did I Do? button to see your score.

1. In this lesson you learned that Antarctica is the world's largest desert. Think back to previous lessons to answer this question: why isn't the Arctic considered a desert?
   
   

2. What do all deserts have in common?
   
   

3. Can desertification occur in areas that are not naturally deserts?
   
   

4. What are some things people are doing to prevent desertification?
   
   

5. Can desertification be reversed?
   
   

6. What are some natural factors that cause some areas to receive little precipitation?
   
   

7. What are some ways that humans cause desertification?
   
   

8. Have the great deserts of the earth significantly grown or shrunk because of human activities?
   
   

9. What are the two main forces that cause erosion?
   
   

10. How are the Gobi Desert and Antarctica similar?