Something to Remember - World of Vertebrates

Mammals   
1. make milk
2. hair
3. limbs (two or four)
4. warm-blooded
5. breathe with lungs
6. born alive   

Fish   
1. breathe with gills
2. fins
3. cold-blooded
4. scales
5. hatch from eggs
   
Amphibians   
1. breath with gills when young
2. breath with lungs when older
3. all amphibians have smooth, moist skin
4. amphibians lay eggs
5. cold-blooded
6. have no hair
7. begin life in water
examples: frogs, toads, and salamanders   

Reptiles   
1. breath with lungs
2. dry, scaly skin (but not turtles)
3. cold-blooded
4. most lay eggs
5. begin life on land
examples: snakes, lizards, turtles, crocodiles, and alligators   

Birds   
1. have feathers
2. have wings
3. hatch from eggs
4. have two legs
5. have a beak or bill
6. hollow bones
7. breathe with lungs
   
Cold-blooded   
body temperature changes when the temperature of the environment changes   

Vertebrate   
animals with backbones

Invertebrates    animals without backbones   

Warm-blooded   
body temperature stays just about the same no matter the outside temperature   

Skeleton   
the bones which form the framework of a body