| A | B |
|---|
| primate* (n) | a type of animal species that includes apes, monkeys and humans |
| vertebrate (n) | an animal with a backbone |
| cold-blooded (adj) | used to describe animals that must find warmth or coolness through their environment |
| fish (n) | 1 of the categories of vertebrates; they have scales and fins; they breathe using gills, and lay soft eggs in water |
| amphibians (n) | 1 of the categories of vertebrates; they are covered with smooth, moist skin; have 4 limbs; breathe using gills when young and lungs when adults; lay soft eggs in water |
| reptiles (n) | 1 of the categories of vertebrates; they are covered in tough, hard scales; most have 4 limbs; breathe using lungs; lay eggs with rubbery shells on land |
| birds (n) | 1 of the categories of vertebrates; they have feathers and 4 limbs; breathe using lungs; lay eggs with hard shells on land |
| mammals (n) | 1 of the categories of vertebrates; they have bodies covered with hair; have 4 limbs; breathe using lungs; their young develop inside their bodies, so they do not lay eggs; feed their young on milk |
| warm-blooded (adj) | animals that have body temperatures that stay the same regardless of their environment |
