Science Unit 4 Animals

Science

Unit 4: Living Things and Habitats

Animals

How do we classify animals?

When you classify, you group animals or things that are alike. Scientists classify animals into several groups. In some groups, animals have backbones. In some groups, animals do not have backbones.

Vertebrates

Animals that have backbones are called vertebrates.

Mammals

A mammal is a warm-blooded animal (as a dog, mouse, bear, whale, or human being) with a backbone that breathes air and that feeds its young with milk produced by the mother. They have skin usually more or less covered with hair.

Amphibians

Amphibians are animals that live the first part of their lives in the water and the last part on the land. When they hatch from their eggs, amphibians have gills so they can breathe in the water. They also have fins to help them swim. Their skin is smooth and slimy. Amphibians are cold-blooded. Frogs, toads and salamanders are amphibians.

Birds

Birds are warm-blooded animals that have feathers, wings, and beaks or bills. Although all birds have wings, a few species can't fly. They lay eggs and have lungs. Eagles, ostriches and penguins are types of birds.

Reptiles

Reptile is a cold-blooded animal (as a snake, lizard, turtle, or alligator) that breathes air and usually has the skin covered with scales or bony plates. Most reptiles lay eggs but others are born.

Fish

A Fish is an animal that lives in water and has fins for swimming and gills for breathing. Fish are cold-blooded animals with skeletons inside their bodies. Most fish have scales on their skin. There are many kinds of fish, including salmon, goldfish, tuna, and sharks.

Invertebrates

Animals that do not have a backbone are called invertebrates.

Invertebrates

There are many kinds of animals that do not have backbones. Some of these animals have shells or hard body coverings that help keep them safe.

Invertebrates

Some animals without backbones do not have shells. They have soft bodies. These animals must use other ways to stay safe.

Let's Review!

Classify the animals in vertebrate or invertebrate.

invertebrate

vertebrate

Classify the animals.

___________

___________

__________

_________

__________

mammal

reptile

amphibian

bird

fish

Keep practicing!