| A | B |
|---|
| vertebrates | animales that have a backbone |
| invertebrates | animals that do not have a backbone |
| mammals | have hair and produce milk for their young |
| reptiles | have dry, scaly skin |
| amphibians | have moist skin and no scales; most of them begin life in water, but live on land as adults |
| fish | live their entire lives in water; most have hard scales that cover their bodies and gills to take oxygen from the water |
| birds | vertebrates with feathers |
| inherited trait | a characteristic that is passed from parent to baby |
| learned behavior | are learned from their parents |
