1. Unit 3 Lesson 3 How Are Animals Different?
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2. All Kinds of Animals Animals have different shapes and sizes.
Unit 3 Lesson 3 How Are Animals Different?
All Kinds of Animals
Animals have different shapes and sizes.
They have body parts that help them move in different ways. Some animals walk and run. Others fly or swim.
Animals have different body coverings. Some have fur or hair. Others have scales or feathers.
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3. Ways to Group Animals You can group animals by their body coverings.
Unit 3 Lesson 3 How Are Animals Different?
Ways to Group Animals
You can group animals by their body coverings.
You can group animals by how they move.
You can group animals by their size.
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4. Mammals A mammal has fur or hair.
Unit 3 Lesson 3 How Are Animals Different?
Mammals
A mammal has fur or hair.
Most mammals have live young. A young mammal drinks milk from its mother’s body.
People are mammals. Golden lion tamarins, giant anteaters, and jaguars are also mammals.
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5. Unit 3 Lesson 3 How Are Animals Different?
Birds
A bird has feathers. Birds also have a beak and wings. Most birds use wings to fly.
Birds lay eggs. They find food to feed their young.
Quetzals, toucans, and parrots are all birds.
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6. Unit 3 Lesson 3 How Are Animals Different?
Reptiles
A reptile has dry skin. It is covered in scales. Most reptiles lay eggs.
Most reptiles have four legs. Turtles may have legs or flippers. Snakes are reptiles with no legs.
Green iguanas and caimans are also reptiles.
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7. Unit 3 Lesson 3 How Are Animals Different?
Amphibians
Most amphibians have smooth, wet skin. Some amphibians, such as toads, have rough, bumpy skin.
Amphibians lay their eggs in water. Young amphibians live in the water. When they are grown, they live on land.
A poison dart frog and a cane toad are amphibians.
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8. Fish A fish has body parts that help it live in water.
Unit 3 Lesson 3 How Are Animals Different?
Fish
A fish has body parts that help it live in water.
Most fish have scales that help keep their bodies safe. Fish have fins to swim. They have gills to take in oxygen.
Red piranha and silver dollar fish have scales, fins, and gills.
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9. Unit 3 Lesson 3 How Are Animals Different?
Insects
An insect has three body parts and six legs. A hard shell keeps its body safe.
Some animals look like insects, but they are not. A spider has eight legs. It is not an insect.
Grasshoppers, butterflies, and rhinoceros beetles are all insects.
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