EHow Can We SSENTIAL QUESTION Classify Vertebrates? · SC.3.L.15.1arthropods, vertebrates and invertebrates, those having live births and those which lay eggs) Classify animals into

ACTIVE READING

Engage Your Brain

ESSENTIAL QUESTION

How Can We Classify Vertebrates?

Lesson VocabularyList each term. As you learn about each one, make notes in the Interactive Glossary.

Signal Words: ComparisonSignal words show connections between ideas. Words that signal comparisons, or similarities, include like, alike, same as, similar to, and resembles. Active readers remember what they read because they are alert to signal words that identify comparisons.

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yLESSON 2SC.3.L.15.1 Classify animals into major groups (mammals, birds, reptiles, amphibians, fish,

arthropods, vertebrates and invertebrates, those having live births and those which lay eggs)according to their physical characteristics and behaviors. SC.3.N.3.2 Recognize that scientists use models to help understand and explain how things work.

Find the answer to the following question in this lesson and record it here.

How would you classify this animal?

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Have a Backbone!

What do you have in common with fish, alligators, frogs, birds, and seals? Why, it’s your backbone!

ACTIVE READING As you read these two pages, find and underline the definition of vertebrate.

Lions live in grasslands. Their young are called cubs.

Some boas live in thick forests. Their backbones let them curl up and stretch out!

Animals that have a backbone are called

vertebrates. There are many kinds of

vertebrates. Frogs, birds, snakes, and tigers

are all vertebrates. Vertebrates live in many

places.

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DO THE MATH

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This bass lives in fresh water. Like most kinds of fish, it lays eggs.

FishFish are vertebrates, too. Fish are

many sizes, shapes, and colors. Some

fish are tiny. Other fish, such as the

whale shark, are large. A whale

shark can grow as long as a school

bus! Fish take in oxygen through

their gills and spend their whole

lives in water.

Measure in Centimeters

Alexa’s goby is about 3 centimeters long. Draw a fish this long.

Samuel’s goldfish is 6 centimeters long. Draw a fish this long.

This fish

lives deep in

the ocean where

there is no light.

Sea Horse

Monkf ish

Bass

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Amphibian or Reptile?How are amphibians and reptiles different? Read on to learn about these two groups.

ACTIVE READING As you read these two pages, draw circles around the clue words that signal when things are being compared.

This amphibian lives around water.

This reptile lays eggs.

Amphibians [am•FIB•ee•uhnz]

start life in water. Many amphibians

move to land as they grow.

Salamanders, toads, and frogs

are amphibians. Like most other

amphibians, frogs lay their eggs

in water. When the eggs hatch,

the tadpoles look like fish. Most

amphibians have smooth, moist skin.

Young amphibians have gills. Many

adult amphibians have lungs.

Reptiles are animals with scales

covering their bodies. Lizards

and turtles are reptiles. Similar to

amphibians, most reptiles hatch from

eggs. A reptile breathes with lungs its

whole life. Reptiles, such as crocodiles,

that spend a lot of time in water must

come up for air.

Frog

Turtle

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Alligators are covered with large scales. They lay eggs in nests.

Geckos are covered with scales. They

breathe using lungs.

Mudpuppies have smooth, moist skin.

Identify Read the facts on each trading

card. In the circles, write an “A” for amphibian or an “R” for reptile. Then color the borders green for reptiles or orange for amphibians.

Alligator

Gecko

Mudpuppy

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Bee-eaters

have colorful feathers.

Bee-eater

Penguin

Birds and MammalsWhat are some other vertebrate groups? Read to find out.

ACTIVE READING As you read these two pages, underline three characteristics of birds and circle three characteristics of mammals.

Flamingos live in places with

shallow water.

Birds are another kind of vertebrate. Birds

are animals that have wings, feathers, and

beaks and lay eggs. Some birds, such as the

hummingbird, are tiny. Other birds, such as

the ostrich, are very large. Birds breathe

with lungs.

Owl

Flamingo

Golden Pheasant

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Can you tell why this animal is called a bearded seal?

Bearded Seal

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Kangaroo

Elephants, apes, whales, and

dolphins are all mammals. How are

they alike? Mammals are animals

that have fur or hair. Most do not

lay eggs. Instead, female mammals

give birth to live young and make

milk to feed them. Mammals also

use lungs to breathe.

Draw your own bird or mammal card. Label its characteristics.

This monkey

has hair covering

its body.

Emperor Tamarin

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Sum It Up

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Write the animal type on the line and then draw a line to

the matching picture.

A lives in water

and takes in oxygen through gills.

A has fur or

hair covering its body and gives

birth to live young.

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A lives on land

or in water and has scales.

A has feathers

and wings.

An has moist

skin and begins life in the water.

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Brain CheckName

Vocabulary Review

1

LESSON 2

Complete the maze to connect each animal to its classification at the

bottom. Pass through each animal’s traits along the way.

live whole life in water

take in oxygen through gills

live in or near waterfeed milk to young

moist skin

skin with scales

hair of fur

vertebrate

feathers

wings

mammal reptile fish bird amphibian

goldfish salamander snake hippo owl

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Take It

HomeShare what you learned about types of animals with a family member. Together, name and describe the fish, reptiles, amphibians, birds, and mammals you have seen or know about.

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3

4

You are hiking along a river. You see an animal that looks like it could be either

a lizard or a salamander. What are questions you could ask the guide to help

you decide which animal it is?

Draw an imaginary bird. Label the parts that make it a bird.

Place an X on the animals that lay eggs.

buffalo newt ostrich salmonlizard

Apply Concepts

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