1. Chapter 3

2. 1. amphibians

3. 2. bilateral symmetry

4. 3. a. pollution
b. souvenir hunters
c. ships and boats

5. 4. reptile

6. 5. bilateral symmetry

7. Radial symmetry

8. 7. none

9. 8. Centipedes have 1 pair of legs per a segment
8. Centipedes have 1 pair of legs per a segment. Millipedes have 2 pairs of legs per a segment.

10. 9. Coral reefs are made up of colonies of polyps that leave behind cup shaped skeletons when they die.

11. 10. Reptiles are cold-blooded and lay eggs
10. Reptiles are cold-blooded and lay eggs. Waterproof skin, breathing through lungs, and tough shells on eggs help them live on land.

12. 11. It helps us identify patterns and relate past animals to present ones.