Mammals
Milk.
Birts have __ not hair or fur.
feathers
Fish don't have arms and legs. They use their __ and __ to swim.
fins and tails
Reptiles can live on ___ or in the ___.
land water
Most mammals have ___ or ___ on their bodies.
hair or fur
Birds hatch from __.
eggs.
Fish can change the temperature of their blood, so they are __ blooded.
cold
Cold blooded
Do mammals hatch from eggs?
No, they are born alive.
beak
Fish are the only vertebrates that spend their whole life in _____.
water
A frog is a(n) ___.
amphibian
Mammals breathe with __.
Lungs
Birds have ___ bones so they are light enough to fly.
hollow
Some fish, like sharks, have soft bones made of __.
cartilege
After they hatch, frogs grow tails and are called __.
tadpoles
Mammals have backbones. What is another name for backbone?
spine
Birds have __ instead of front legs.
wings
gills
An alligator is a ___.
reptile