Next Generation Science Level 1 - Textbook A

Science for the Next Generation

Science Gra d e On e

Textbook

A

The 5E Model – Guided Inquiry The Next Generation Science series is based on the Biological Sciences Curriculum Study (BSCS) 5E teaching and learning instructional model.

The 5E model is centered on the idea that students understand science concepts best by using prior knowledge to pose questions and find answers through guided inquiry.

This hands-on approach, integrated with engineering and design skills, has students learn science by doing science. Teachers guide the learning process and are able to assess student performance by evaluating student explanations and the application of newly acquired knowledge and skills.

Engage

The Engage phase of the 5E model provides students with the opportunity to demonstrate their prior knowledge and understanding of the topic or concept. Students are presented with an activity or question which serves to motivate and engage students as they begin the lesson. Teachers identify and correct any misconceptions and gather data from students which will guide informed teaching and learning.

Essential to stimulating and engaging students is the use of mixed media such as colorful photos, illustrations and diagrams found throughout the textbooks and activity books. Next Generation Science also includes extensive digital resources such as narrated videos, interactive lessons, virtual labs, slideshows and more.

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Explore

This phase encourages exploration of concepts and skills through handson activities and investigations. Students are encouraged to work together and apply various process skills while gaining concrete, shared learning experiences. These experiences provide a foundation for which students can refer to while building their knowledge of new concepts. This studentcentered phase comes before formal explanations and definitions of the concept are presented by the teacher.

Explain

This phase follows the exploration phase and is more teacher-directed.

Students are initially encouraged to draw on their learning experiences and demonstrate their understanding of the concept through explanations and discussion. After the students have had the opportunity to demonstrate their understanding of the concept, the teacher then introduces formal definitions and scientific explanations. The teacher also clarifies any misconceptions that may have emerged during the Explore phase.

Elaborate

In the Elaborate phase, students refine and consolidate their acquired knowledge and skills. Opportunities are provided for students to further apply their knowledge and skills to new situations in order to broaden and deepen their understanding of the concept. Students may conduct additional investigations, share information and ideas, or apply their knowledge and skills to other disciplines.

Evaluate

This final phase includes both formal and informal assessments. These can include concept maps, physical models, journals as well as more traditional forms of summative assessment such as quizzes or writing assessments.

Students are encouraged to review and reflect on their own learning, and on their newly acquired knowledge, understanding and skills.

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Next Generation Science Next Generation Science is based on the United States Next Generation Science Standards (NGSS). The series consists of full-color textbooks and full-color activity books for Grades K to 6.

Need and

Next Generation Science engages students with a highly visual presentation of the disciplinary core ideas in the textbooks and places an emphasis on applying scientific knowledge using NGSS practices through numerous scientific investigations. Next Generation Science sees engineering as an essential element of science education and as such is tightly integrated into both the textbooks and activity books.

Anima living food,

Some for fo anim both

The Next Generation Science textbooks include the following features:

Think Deeply Topic-related questions for group discussion aimed at deepening students’ understanding of the topic.

In the Field

Can you imagine what it would be like to travel into space? What would the Earth look like from space? How would it feel to walk on the moon?

12 as far as the In the past, astronauts have traveled moon. As science and technologies advance, we are looking to venture further into space. Maybe you will be the first astronaut to travel all the way to Mars!

A person that travels into space is called an astronaut. Astronauts spend many years studying and training. Astronauts help us to learn more about space and the objects in our solar system.

Engineer It! Goes beyond inquiry by encouraging students to design, model and build to engineer solutions to defined problems.

In the Field Inspirational sciencerelated professions to stir interest in sciencerelated careers.

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A Closer Look

105

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A Closer Look Invokes enthusiasm in science by presenting interesting topics beyond the syllabus.

Chameleons

Chameleons are lizards that have spec ial body parts that help them to survive in the place they live.

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Amazing Fact!

Interesting facts to build interest and enthusiasm.

Did You Know?

Animals and people drink the water they need.

ds of Animals People

als and people are things. They need water and air.

e animals eat plants ood. Others eat other mals. Some animals eat plants and animals.

How do you get the things you need from day to day.

Try This!

Optional hands-on activities to be conducted in groups or at home.

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Science Words

roots stem leaves flowers fruits fur

Extra information to build students’ knowledge base of the current topic.

People and land animals breathe in the air around them. Some animals, like fish, are able to get the air they need from water.

2. Describe two ways roots help

feathers scales lungs gills respond

3. True or false. (a) The roots hold the seeds for the plant. (b) Leaves use water, air and sunlight to mak e food for the plant.

4. Copy and complete the Body Covering

Review

1. Use the words in the box fruit

roots

stem

leaves

table.

Animal 1

Hair or Fur

to label the picture.

Animal 2

Feathers

flower

(d)

(a)

a plant.

7. (e)

Describe how a wire fenc e is similar to the blackberry bush.

(c) They have a long, stick y 54 tong ue that they shoot out to catch food such as insec ts.

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Chameleons have curle d tails which help them to hold on to tree branches.

Some chameleons can change the color of their skin. This helps them to blend in with their surro undings and avoid being spotted by predators such as birds .

Review 45

Links students to the Next Generation Science Activity Book at the appropriate juncture.

Scales or Shell 5. Which body part do fish use to breathe in water?

6. Describe one way an animal can respond to changes in its surroundi ngs.

(b)

AB Activity

Topical questions at the end of each chapter for formative assessment.

Discussion Topic-related questions and situations for class discussion to build a deeper understanding of topics.

Science Words Lists the essential science vocabulary covered in each chapter.

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Contents Unit 1 – Living and Non-living Things Living Livings Non-living Things Review

Unit 2 – Plant and Animal Parts Plant Parts Animal Parts Responding to Change Mimicking Nature Review

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2 4 14 16

18 20 32 48 50 52

Unit 3 – Parents and Offspring Plant Life Cycles Animal Life Cycles Similar and Different Parents and Their Young Review

56 58 60 68 72 80

Unit 4 – Earth and Space Patterns

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Stars and the Sun Around the Earth Movement of the Earth Earth and the Moon The Solar System Review

86 90 92 98 100 104

Unit 5 – Weather and Seasons Describing Weather Measuring Weather Extreme Weather Seasons Review

108 110 112 118 124 138

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Science Skills

Scientists use special skills to learn about the world around them.

Let’s look at how you can use these skills so you can be a scientist too.

Observe You observe when you gather information about something using your senses. You can observe how something looks, feels, sounds, smells or tastes.

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What senses are the children using to observe?

You can use different tools to observe things closely.

You can use a hand lens, binoculars or a telescope.

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Compare You compare things when you observe and tell how things are similar or different.

How are the hen and chick similar? How are they different?

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Classify When you compare two or more things, you can classify them into groups based on ways they are similar.

How have the leaves been classified into groups?

Leaves in the Garden

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Measure You measure when you find the size or amount of something.

You can use tools to help you measure things. You can use a ruler to compare and measure length.

You can use a balance to compare and measure mass.

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Make a Model You can make a model to test or see how something works.

You can make a model by drawing a picture.

You can also make a model by using the things around you to make a smaller version of something to show how it works.

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Infer You infer when you make a guess about something based on what you know or what you observe.

What can you infer about the cause of the holes in the leaf?

What can you infer from observing the tracks in the sand?

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Communicate You communicate when you tell or show other people what you find out.

You can communicate by making charts, drawing pictures or writing about what you find out.

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Science Investigations Ask Questions

Before a science investigation, ask questions about what you would like to find out.

Make a Prediction A prediction is a guess about what you will observe before you make the observation.

What are some things you would like to find out about in science?

Will a plant grow better in sunshine or darkness?

What do plants need to live and grow?

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A plant will grow better in sunlight.

Plan and Carry Out an Investigation Make a plan with steps that others can follow.

List all the materials you will need.

Procedure

Materials

1. Measure the heights of the plants.

2. Put one plant near a window. Put the other plant in a dark cupboard.

3. Water and observe the plants every day for one week.

two plants

ruler spray bottle with water

Observe and Record Data Record the things you observe. You can write or draw the things you observe. You can use charts and tables.

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Analyze and Interpret Data You analyze when you look closely at recorded data.

You interpret when you understand and explain what the data means.

Make a Conclusion and Communicate Make a conclusion and communicate it to others.

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Science Safety

Follow these safety rules when carrying out investigations.

Wear safety gear.

Follow your teacher’s instructions.

Keep your workspace clean.

Be careful with sharp objects.

Wash your hands after every activity.

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1

Living and Non-living Things

In this chapter you will ...

• distinguish living things from non-living things.

• list the needs of living things.

• list the characteristics of living things.

What do living things need?

2

Go Online!

Access interactive content relating to this topic on the NGScience website. ngscience.com

How can you tell if something is a living thing?

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Living Things

What Are Living Things?

Look out of a window. What things do you see? Some of the things you see are alive.

Something that is alive is called a living thing.

Plants and animals are living things. You are a living thing too.

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Living things need food, water and air to live and grow.

Some of the things around you are not alive. They are called non-living things.

Non-living things do not need food, water or air.

AB

Activity 1.1

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Needs of Plants Like all living things, plants need food, water and air.

Many plants take in water from the soil using roots. They take in air through their leaves.

What happens if a plant does not get the things it needs?

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Plants also need sunlight.

They use the energy from sunlight to make the food they need.

AB Activities 1.2 – 1.3

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Needs of Animals and People Animals and people are living things. They need food, water and air.

Some animals eat plants for food. Others eat other animals. Some animals eat both plants and animals.

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Animals and people drink the water they need.

People and land animals breathe in the air around them. Some animals, like fish, are able to get the air they need from water.

How do you get the things you need from day to day?

AB

Activity 1.4

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Living Things Move Living things move. Animals and people can move from place to place.

Go Online!

Watch a video about the different ways animals move on the NGScience website.

QuickCode: A1A1

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Some animals crawl, walk or run. Some live in water and move about by swimming. Other animals, like many birds, can fly.

AB

Activity 1.5

Plants cannot move from place to place, but there are things moving inside the plant.

Some plants can move their parts.

The Venus flytrap closes its leaves to trap insects.

The mimosa plant closes its leaves when touched.

Think Deeply Some plants move their leaves to face the Sun. How does this help the plant?

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Living Things Grow and Reproduce Living things make new living things just like themselves.

They reproduce and grow.

Many plants grow from seeds. Young plants grow and change as they get older.

They look more and more like the parent plants.

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Animals reproduce too. Some animals look a lot like their parents when they are born. Other animals look different from their parents.

As they grow, they change to look more like their parents.

AB

Activities 1.6 – 1.7

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Non-living Things

What Are Non-living Things?

Non-living things are not alive.

They do not need food, water or air.

What non-living things can you see? How do you know they are non-living things?

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Non-living things cannot move by themselves. They cannot reproduce. They do not grow and change.

AB

Activities 1.8 – 1.10

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Science Words

living thing non-living thing food water air

sunlight move grow reproduce

Review

1. List three living things.

2. List three non-living things.

3. Use a Venn diagram to compare the needs of plants and animals.

4. True or false. (a) Plants use the energy in sunlight to make food. (b) Plants eat other plants for food.

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5. Tell how the animals move. (a) (b)

(c) (d)

6. How does a plant change as it gets older?

7. How does an animal change as it gets older?

8. Use a Venn diagram to compare living and non-living things.

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2

Plant and Animal Parts

How do the different parts of plants help them get the things they need to survive?

Go Online!

Access interactive content relating to this topic on the NGScience website. ngscience.com

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In this chapter you will ...

• list and describe the functions of the parts of a plant.

• list and describe the functions of animal body parts.

• explain how plants and animals respond to changes.

• provide examples of how people mimic plants and animals to solve real-world problems.

How do people mimic nature to help solve problems?

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tomato plant

Plant Parts

Plants have different parts. Each part helps the plant to get the things it needs to survive.

Many plants have roots, a stem and leaves.

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Go Online!

Label the parts of different plants on the NGScience website.

QuickCode: F1K6

tomato fruits tomato flower

Many plants also have flowers and fruits.

How does each plant part help the plant to get the things it needs?

AB

Activity 2.1

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Try This!

Use your fingers to trace the path water takes from the roots to the stem.

Roots

Many plants have roots.

The roots grow down into the soil. They take in the water and nutrients the plant needs.

How is the shape and structure of roots suited to their function?

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Some plants have roots that branch out in all directions. Other plants have long, thick roots that go deep into the soil.

Along with taking in water, roots also help to hold the plant in the soil.

AB

Activities 2.2 – 2.3

Go Online!

Observe roots growing on the NGScience website.

QuickCode: E6U3 Did You Know?

People eat the roots of many different plants. Carrots, beetroots and radishes are all root vegetables. Can you think of others?

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Stems Try This!

Use your fingers to trace the path water takes from the roots, through the stem, to the leaves.

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The stem is the part that holds up the plant.

The water and nutrients taken in by the roots move through the stem to the leaves.

The stem holds up and spreads out the leaves so they can get the sunlight they need.

The stem also supports the fruits and flowers.

How is the shape and structure of a stem suited to its function?

AB

Activity 2.4

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Leaves Think Deeply What do you think would happen to a plant if you took off all its leaves?

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The leaves are the parts that use sunlight, air and water to make food for the plant.

Leaves come in many different shapes and sizes. Many leaves are often flat and thin. This helps them to take in more sunlight.

Think Deeply Some cacti have sharp, spiky leaves.

How does this help a cactus?

The food made in the leaves is moved to all parts of the plant.

How is the shape and structure of a leaf suited to its function?

AB

Activity 2.5

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Flowers

Many plants have flowers.

Flowers come in many different shapes, sizes and colors.

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The flower is the part of the plant that makes seeds. The seeds can grow into new plants.

Insects and other small animals often feed on a sweet liquid, called nectar, made by the flower.

How do the insects feeding on a flower help the plant?

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Fruits

Flowers may grow into fruits. The fruit is the part of the plant that grows around the seeds. They help to protect the seeds.

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Animals often eat fruits.

This can help to move the seeds to new places.

In its new place, a seed can grow into a new plant.

AB

Activities 2.6 – 2.8

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Animal Parts There are many different kinds of animals on Earth. Animals can have different parts that help them get the things they need.

Animal Movement

Unlike plants, animals cannot make their own food. They need to move from place to place to find food and water.

What are some ways animals move? What body parts do they use to move?

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Amazing Fact!

Cheetahs are the fastest animals on land. They can run at speeds of more than 100 kilometers per hour!

Many animals that live on land have legs to move.

Animals with legs can move by walking, running, jumping or crawling.

Make a list of animals with legs. Describe or act out how each animal moves.

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Many animals live underwater.

They have body parts, such as fins and flippers, to help them swim.

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What body part do all the animals on this page have?

How do the animals move?

Some animals, such as bats, birds and many insects, have wings.

They use their wings to fly.

AB

Activity 2.9

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Animal Body Coverings

Animals can have different body coverings to help them survive in the place they live.

Animals such as pandas, monkeys and rabbits have bodies covered with hair or fur.

What are some other animals with hair or fur?

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feathers

Birds are the only animals with a body covered in feathers.

Think Deeply

Feathers are light and help many birds to fly.

Penguins have feathers, but they cannot fly.

How do feathers help a penguin?

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fish scales

Fish, lizards and snakes have bodies covered with scales. A sea turtle has a hard shell.

Scales and shells help to protect the animals. snake scales

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Frogs, toads and salamanders live part of their lives in water and part on land. They often have smooth, moist skin.

AB

Activity 2.10

smooth, moist skin

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Getting Air

Animals need air. Many animals on land breathe in air using lungs.

Animals such as seals and whales live in water. They must come to the surface often to breathe in air.

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Go Online!

Mudskippers spend part of their day in water and part on land. Find out how they get the air they need on the NGScience website.

QuickCode: Z4U8

Fish do not have lungs.

They have special body parts called gills that allow them to breathe underwater.

gills

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Getting Food

Animals have body parts to help them get the food they need to survive.

An eagle has wings and sharp claws to help it catch fish and other animals.

A hummingbird uses it long, thin beak to reach food deep inside flowers.

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A chameleon has a long sticky tongue. It shoots out its tongue to catch insects.

How do these animals’ body parts help them to get food?

AB

Activities 2.11 – 2.12

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A Closer Look

Chameleons Chameleons are lizards that have special body parts that help them to survive in the place they live.

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They have a long, sticky tongue that they shoot out to catch food such as insects.

Chameleons have curled tails which help them to hold on to tree branches.

Some chameleons can change the color of their skin. This helps them to blend in with their surroundings and avoid being spotted by predators such as birds.

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Protection Some animals have special body parts that help protect them from other animals.

Engineer It! Design and build a kangaroo pouch to keep a joey safe.

A pangolin has a body covered in hard scales.

When in danger, a pangolin rolls into a tight ball.

How do the spikes on an anteater help it to stay safe?

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Look closely at the pictures on this page. Can you see the animals in each picture?

Some animals have body coverings that match their surroundings. This can help them hide from other animals.

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Responding to Change Animal Responses

Animals use their eyes, ears, noses and skin to gather information about their surroundings.

When an animal detects a change, it responds to the change to help it survive.

If an animal feels it is too hot in the Sun, it can move to the shade.

If an animal senses danger, it can move to a safer place.

In what other ways do animals respond to changes around them?

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mimosa leaves

Go Online!

Plant Responses Plants also respond to changes around them.

Visit the NGScience website to observe how plants respond to changes around them.

QuickCode: Y9E4

The mimosa plant has leaves that close when touched. Other plants have leaves or flowers that open or close at different times of the day or night.

A sunflower plant moves its leaves to follow the movement of the Sun in the sky.

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Mimicking Nature Scientists often observe plants and animals to get ideas for solving problems. They can copy plant and animal body parts and shapes.

The shape and body parts of a bird can help people to design and build an airplane.

In what ways is a bicycle helmet similar to the shell of a turtle?

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Scientists observed how seeds stick to the fur of animals. They used this idea to invent hook and loop fasteners that hold things together.

AB

Activity 2.13

Engineer It! Design and build a useful tool based on what you know about plant parts.

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Science Words

roots stem leaves flowers fruits fur

feathers scales lungs gills respond

Review

1. Use the words in the box to label the picture. fruit

roots

stem

leaves (d)

(a)

(b) (e) (c) 52

flower

2. Describe two ways roots help a plant.

3. True or false. (a) The roots hold the seeds for the plant. (b) Leaves use water, air and sunlight to make food for the plant.

4. Copy and complete the table.

Body Covering

Animal 1

Animal 2

Hair or Fur Feathers Scales or Shell 5. Which body part do fish use to breathe in water?

6. Describe one way an animal can respond to changes in its surroundings.

7.

escribe how a wire fence is similar to the D blackberry bush.

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In the Field

Scientists often study living things to find ways to solve problems for people.

A biomedical engineer uses what he or she learns from living things to create new things to help people who are sick or injured. Biomedical engineers use science and technology to create artificial limbs and even parts to replace things inside our bodies.

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Biomedical engineers continue to learn from living things. They apply what they learn to test and improve their designs.

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3

Parents and Offspring

In this chapter you will ...

• explain ways in which offspring can be similar or different from their parents.

• describe ways in which parents and offspring engage in behaviors that help the offspring to survive.

How are young plants and animals similar to their parents? How are they different?

Go Online!

Access interactive content relating to this topic on the NGScience website. ngscience.com

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What are some ways animals care for their young?

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Plant Life Cycles All of the stages of a living thing’s life make up its life cycle.

A bean plant grows from seeds. When a bean seed gets the things it needs, it starts to grow into a small plant called a seedling. A seedling has roots and leaves. b ean seeds

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The seedling grows into an adult plant.

b ean flowers and fruits

An adult bean plant will develop flowers and fruits.

The flowers and fruits produce the seeds from which new plants can grow.

AB Activities 3.1 – 3.2

b ean seedling

How does the bean plant grow and change as it gets older?

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Animal Life Cycles Mammal Life Cycle

A female adult elephant gives birth to a baby elephant. The baby elephant looks like its mother. It has four legs, a trunk and a tail.

The baby elephant gets bigger and taller as it grows. It looks more and more like its mother. As an adult elephant, it will produce new young of its own.

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A female adult cheetah gives birth to live young. The young look similar to their parents.

The young grow and change as they get older. As they grow, they look more and more like their parents.

As adult cheetahs, they will produce new young of their own. adult cheetah

young cheetahs 61

Chicken Life Cycle Chickens reproduce by laying eggs. A newborn chicken, called a hatchling, hatches from each egg. The hatchling has the same body parts as its parents.

eggs

adult chicken 62

The hatchling grows into a chick.

The chick grows into an adult chicken and will produce offspring of its own.

Go Online!

Learn more about the life cycle of a chicken on the NGScience website.

QuickCode: F8U8

hatchling

chick

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Frog Life Cycle Adult frogs lay eggs in water.

The young that hatches from an egg, called a tadpole, does not look like an adult frog.

A tadpole has a long tail. It uses gills to breathe in water.

Go Online!

Observe the life cycle of a frog on the NGScience website.

QuickCode: B6S4

A tadpole grows into a froglet.

Its tail gets smaller and it starts to grow legs. Its gills change into lungs. It starts to look more like its parents.

eggs tadpole 64

The froglet grows into an adult frog and moves from water onto land.

The adult frog will go on to produce young of its own.

How is the life cycle of a frog different from the life cycle of a cheetah? adult frog

froglet

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eggs

chrysalis

caterpillar

Butterfly Life Cycle Go Online!

Observe the life cycle of a butterfly on the NGScience website.

QuickCode: D4E5

Adult butterflies lay eggs.

The young that hatch from the eggs are called caterpillars.

A caterpillar does not look like its parents. It has a worm-like body and no wings.

When it is ready, a caterpillar changes into a chrysalis.

Inside the chrysalis, its body changes form.

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adult butterfly

Did You Know?

AB

Activity 3.3

During its life cycle, a butterfly’s body changes completely.

This complete change in body form is called metamorphosis.

When the young emerges from the chrysalis, it has all of the parts of an adult butterfly. As an adult, it will go on to have young of its own.

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Similar and Different Similar to Parents Try This!

Find a young plant growing in the same area as its parent.

Create a chart to show how the young and parent are the same and how they are different.

When plants and animals have offspring, the young often look similar to their parents.

A young tomato plant looks like its parents. It has roots and a stem.

The leaves are the same shape as its parents.

As the young plant grows, it will produce tomato flowers and fruits just like its parents.

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Young bear cubs look a lot like their parents. They have a body covered in brown fur. They have four legs with sharp claws.

How will the bear cubs change as they get older?

AB

Activity 3.4

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Different from Parents Young can also be different from their parents.

Young sunflower plants are shorter and have fewer leaves than their parents.

As they grow, they look more like their parents.

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Young kittens have the same body parts as their parents, but they are also different.

Young kittens are smaller than their parents. They may have different colors.

How are the young goslings different from their mother?

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Parents and Their Young

To live and grow, all animals need water and food. They also need shelter. Parents often help their young to get the things they need to survive.

Think Deeply How do young animals communicate with their parents to let them know when they are hungry?

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An adult lion helps her cubs survive by teaching them how to find water.

A female cat cares for her kittens by feeding them milk.

AB

Activity 3.5

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Caring for Their Young Many young animals cannot get the things they need to survive on their own. They are cared for by their parents.

Engineer It! Design and build your own bird nest that can hold three eggs and keep them safe.

Activity Book: p. 115

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Parents may help keep their young warm or protect them from danger.

Parents may feed their young.

They may teach them where to find water and food.

Parents can provide shelter for their young.

AB

Activity 3.6

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Parents Teach Their Young As young animals grow, they learn things from their parents.

Parents may teach their young how to find food and water.

Parents may teach their young how to stay safe.

What things does a lion teach its young before they go into the wild alone?

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Parents and Their Young Communicate Parents and their young communicate with each other.

Parents may use sounds to warn their young of danger.

Their young may cry or make sounds when they need food or water.

Amazing Fact!

A baby whale, called a calf, uses soft whispers to communicate with its mother to avoid being heard by other animals.

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A Closer Look

Lion Prides Lions often live together in a large group called a pride. In the pride, the lions help each other in different ways.

The adult lions work together to hunt for food, stay safe and raise their young. The young lions learn from the adult lions and also from each other.

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Female lions often stay in the same pride all their lives.

Male lions stay with the pride for about three years, before moving to another pride or starting a new pride of their own.

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Science Words

life cycle seedling offspring hatchling

chick tadpole froglet

Review

1. What is a life cycle? (a) Growing and changing. (b) Having young. (c) All of the stages in a living thing’s life.

2. Which shows the life cycle of a plant? (a) seed seedling adult plant (b) seedling seed adult plant (c) adult plant seedling seed 3. Describe how a seedling changes as it grows.

4. True or false.

Caterpillars look like their parents when they hatch.

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5. Use each word to label the stages in the life cycle of a frog. tadpole frog froglet eggs (a) (b)

(c) (d)

6. In what ways is a young pumpkin plant similar to its parents?

In what ways is it different?

7. In what ways is a duckling similar to its parents? In what ways is it different?

8. List two ways animals care for their young.

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In the Field

If you were amazed by the fascinating changes that take place during the life cycle of a frog, you might want to be a herpetologist. A herpetologist is a scientist that specializes in the study of reptiles and amphibians.

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Herpetologists usually work in nature. They study animals like salamanders, frogs, snakes and lizards.

They work to make sure the animals are safe and healthy in the forests, ponds and other places they live.

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4

Earth and Space Patterns

How do the Earth and the moon move in space?

Go Online!

Access interactive content relating to this topic on the NGScience website. ngscience.com

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In this chapter you will ...

• observe and describe stars.

• describe the movement of the Earth and explain the occurrence of night, day and seasons.

• describe the movement of the moon and explain the phases of the moon.

What causes the Sun to appear to move across the sky?

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a star

Stars and the Sun When you look at the sky on a clear night, what things do you see?

The bright lights you see in the sky are stars. A star is a giant ball of hot gas.

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Observe the sky on a clear night. Describe what you saw to your classmates.

Think Deeply

The stars appear small to our eyes because they are so far away.

If you could see stars up close, you would see that they come in many different sizes, colors and brightness.

AB

The Sun we see in the sky during the day is a star. Why can’t you see the Sun at night?

Activity 4.1

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Our Very Own Star Think Deeply You can feel the heat from the Sun. Why can’t you feel the heat from other stars?

During the day, the Sun lights up the sky. The Sun is a star. It is the closest star to the Earth.

The Sun is very important to all living things on Earth.

How does the Sun affect living things?

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The heat from the Sun keeps living things warm.

The light from the Sun helps people and animals to see.

Plants use the energy in sunlight to make food.

What would the Earth be like if there was no Sun? AB

Activity 4.2

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satellite

Around the Earth Amazing Fact!

The International Space Station (ISS) is the largest man-made object in space. Up to six astronauts can live in the space station.

There are many objects in space. Some objects are close to the Earth. They stay near the Earth because they are pulled by the Earth’s gravity.

Gravity is a force that pulls objects near each other.

space station

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The Earth’s gravity causes some things in space to move in a pattern around it.

Satellites move around the Earth. The moon moves around the Earth too.

moon

space telescope

Go Online!

Observe the movement of objects in space on the NGScience website.

QuickCode: B6X3

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Movement of the Earth Rotation of the Earth The Earth is a very large ball that spins round and round. As it spins, part of the Earth is facing the Sun and is in daylight. Part of the Earth is also facing away from the Sun and it is night.

One complete spin of the Earth is called a rotation.

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It takes the Earth 24 hours (one day) to complete a rotation.

AB Activities 4.3 – 4.5

daytime

Go Online!

Observe the rotation of the Earth on the NGScience website.

QuickCode: X4Y4

night-time

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Sunrise and Sunset Have you ever noticed how the Sun appears to move across the sky during the day?

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sunrise

midday

sunset

The Sun rises in the sky in the morning. It appears to move across the sky, then sets in the evening. The Sun, however, is not moving through the sky.

The Sun appears to move across the sky due to the rotation of the Earth. This causes the Sun to rise in the morning and set in the evening.

AB

Activities 4.6 – 4.7

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Revolution of the Earth

Go Online!

Observe the revolution of the Earth around the Sun on the NGScience website.

QuickCode: Z6F9

As the Earth rotates, it also moves around the Sun. One full trip around the Sun is called a revolution. It takes the Earth 365 days (one year) to complete one revolution around the Sun. As it moves, part of the Earth is leaning toward the Sun and part is leaning away from the Sun.

How do the seasons change as the Earth moves around the Sun?

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During a revolution, the part of the Earth closest to the Sun changes. This predictable pattern of the Earth’s movement causes seasons.

In different seasons, the weather and the number of hours of sunlight are different.

You’ll learn more about the four seasons in the next chapter.

AB

Activity 4.8

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Earth and the Moon The moon often appears very bright in the night sky.

The moon appears bright because it reflects the light from the Sun. Sometimes you can even see the moon during the day.

Like the Sun, the rotation of the Earth makes the moon appear to move across the sky.

The moon also moves in a pattern around the Earth.

It takes the moon about 28 days to complete one revolution of the Earth.

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Think Deeply How many days are there between one full moon and the next? How do you know?

As the moon revolves around the Earth, different amounts of the sunlit side of the moon can be seen. This makes the moon appear to change its shape.

How are we able to predict the part of the moon we will see?

AB

Activity 4.9

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The Solar System

A planet is a large object that moves around, or orbits, a star.

The Earth is a planet. It orbits around the Sun. Including Earth, there are eight planets that orbit the Sun.

Mars Venus

Mercury

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Earth

All of the planets and other objects orbiting the Sun make up our solar system.

AB

Activity 4.10

Go Online!

Observe the movement of the planets in our solar system on the NGScience website.

QuickCode: N8N7

Saturn

Neptune

Uranus Amazing Fact!

Jupiter

Saturn is the second largest planet in the solar system and it has the most moons.

So far, scientists have discovered over 80 moons!

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A Closer Look

Moons You have learned that planets are large objects that orbit the Sun. Similarly, moons are large objects that orbit planets.

Here on Earth, we have one moon that orbits around us.

The Earth is the only planet in the Solar System to have just one moon.

Mercury and Venus, the closest planets to the Sun do not have any moons at all!

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For the remaining planets, their moon totals are: Mars 2, Jupiter 79, Saturn 82, Uranus 27 and Neptune 14.

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Science Words

star Sun gravity Earth

rotation revolution seasons moon

Review

1. What is a star? (a) A planet. (b) A type of moon. (c) A large ball of hot gas.

2. Which star can we see during the day?

3. True or false.

The Sun is a planet.

4. What causes the occurrence of day and night on Earth? (a) The revolution of the Sun. (b) The rotation of the Earth. (c) The revolution of the Earth.

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5. What causes the Sun to appear to move across the sky during the day? (a) The revolution of the Sun. (b) The rotation of the Earth. (c) The revolution of the Earth.

6.

True or false. (a) The moon revolves around the Earth. (b) The Sun revolves around the moon. (c) The Sun revolves around the Earth.

7. What causes the moon to appear to change its shape in the night sky? (a) The rotation of the Earth. (b) The revolution of the moon around the Earth. (c) The revolution of the moon around the Sun. 8. How long does it take for the Earth to complete one full rotation? (a) one year (b) 28 days (c) 24 hours 9. How long does it take for the Earth to complete one revolution around the Sun? (a) one year (b) 28 days (c) one day 105

In the Field

Can you imagine what it would be like to travel into space?

What would the Earth look like from space? How would it feel to walk on the moon?

A person that travels into space is called an astronaut. Astronauts spend many years studying and training. Astronauts help us to learn more about space and the objects in our solar system.

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In the past, astronauts have traveled as far as the moon. As science and technologies advance, we are looking to venture further into space. Maybe you will be the first astronaut to travel all the way to Mars!

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5

Weather and Seasons How can we describe the weather from day to day?

Go Online!

Access interactive content relating to this topic on the NGScience website. ngscience.com

In this chapter you will ...

• describe the weather from day to day.

• list the ways in which scientists measure weather.

• list the types of extreme weather.

• list and describe the four seasons.

• relate the amount of daylight to the time of year.

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How does the weather change from season to season?

How does the amount of daylight change throughout the year?

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Describing Weather Go outside. What words can you use to describe the weather today?

Go Online!

Observe how weather changes from day to day on the NGScience website.

QuickCode: Y7T2

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Weather is what the air and the sky are like outside. We can use different words to describe the weather.

The weather can be hot or cold.

It may be sunny or cloudy. Rain or snow can fall from the sky.

Moving air is called wind.

Sometimes the wind can be strong.

Other times there may be no wind at all.

During a storm, there may be lots of rain and strong winds. There may also be lightning and thunder.

During a storm, it may not be safe to go outside.

AB

Activities 5.1 – 5.2

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Measuring Weather

Scientists use tools to measure weather. Tools can be used to measure how hot or cold the air is. Tools can also be used to measure wind, rain and snow.

Measuring weather and observing weather patterns help scientists to predict the weather.

How is predicting the weather useful?

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Temperature Temperature is how hot or cold the air outside is.

We can measure temperature using a thermometer. The higher the temperature, the warmer the weather.

AB

Activities 5.3 – 5.4

What is the temperature shown on the thermometers? Which temperature is colder?

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Measuring Wind Try This!

Go into the yard and pick some grass or leaves. Throw them into the air and observe the direction they move. Can you tell which way the wind is blowing?

What are some ways scientists measure wind?

You have learned that wind is moving air. Scientists can measure wind in many ways.

A wind vane is an instrument used to measure the direction the wind is blowing.

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An anemometer is a tool that measures how fast the wind is blowing.

How is measuring wind speed useful?

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Measuring Rain and Snow Scientists also use tools to measure the amount of rain and snow that falls.

A rain gauge measures how much rain falls in millimeters or inches.

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Go Online!

Learn more about how we measure weather on the NGScience website.

QuickCode: X6L8

Snowfall can be measured in centimeters, meters, inches or feet.

How is it useful to measure wind, rain and snow?

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Extreme Weather Sometimes the weather may be extreme. Extreme weather can be dangerous. It is important to prepare for and stay safe during extreme weather.

What are some kinds of extreme weather in your area?

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Thunderstorms A thunderstorm is an extreme weather event with strong winds and rain. Lightning can strike buildings, trees and the ground.

Sometimes a thunderstorm can form a tornado. A tornado is a tube of spinning wind that reaches the ground.

Hurricanes A hurricane is a very large storm that starts in the ocean and moves onto land. The strong winds and rain from hurricanes and tornadoes can cause damage to buildings and homes.

AB

Activities 5.5 – 5.6

Amazing Fact!

When lightning strikes, the air around the lightning heats up very quickly. This causes the air to explode.

Thunder is the loud sound made as the air explodes!

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Go Online!

How can you prepare for and stay safe during a wildfire?

Get some tips on the NGScience website.

QuickCode: N9L6

Did You Know?

A wildfire can also be called a rural fire or a bushfire.

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Wildfires During a long period of hot and dry weather, plants can dry out. This can cause them to catch fire easily. This can cause wildfires. A wildfire is a large and uncontrolled fire in nature.

Wildfires can be caused by lightning. They can also start when fires lit by people get out of control.

Wildfires can cause plants and animals to die. They can damage farms and houses.

Think Deeply Wildfires occur most often during summer. Why is this so?

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Droughts and Floods A drought occurs when an area gets much less rain than usual.

During a drought, places that once contained water can dry up.

There may not be enough water for living things to survive.

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A flood occurs when an area gets much more rain than usual. A flood can cause water to overflow from rivers onto land.

Droughts and floods can be harmful to plants, animals and people.

Go Online!

Find out about other types of extreme weather, including heatwaves and tsunamis, on the NGScience website.

QuickCode: Y6Q1

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Seasons

In many places on Earth, the year can be divided into four different seasons. The four seasons are spring, summer, fall and winter.

The weather changes from season to season.

Discuss the weather in your area during each season.

spring

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summer

The seasons are caused by the revolution of the Earth around the Sun. As the Earth revolves, part of the Earth is tilted toward the Sun and gets more sunlight. This part of the Earth is in summer.

Part of the Earth is tilted away from the Sun and gets less sunlight. This part of the Earth is in winter.

AB

Go Online!

Observe how the revolution of the Earth around the Sun causes the changes in seasons on the NGScience website.

QuickCode: P7T5

Activity 5.7

fall

winter

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Spring During spring, the weather is warm and there is lots of rain.

There is also lots of sunlight.

With lots of sunlight and water, plants begin to grow.

Describe the weather in spring in your area.

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The growing plants provide food for many animals.

With lots of food, animals begin to have young.

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Summer Summer is the season that comes after spring. Summer is the hottest season. It is also the season with the most hours of daylight.

There are many sunny days in summer. It may not rain often.

Describe the weather in summer in your area.

AB

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Activity 5.8

With many sunny days, plants grow bigger. Many trees and other plants grow fruits.

Young animals grow into adults.

Did You Know?

The Earth is divided into two parts – the northern hemisphere and the southern hemisphere. When the northern hemisphere is in summer, the southern hemisphere is in winter.

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Fall

Did You Know?

Trees that lose their leaves during fall and grow them back in spring are called deciduous trees.

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Fall is the season that comes after summer. During fall, there are fewer hours of daylight compared to summer.

The temperature gets cooler.

The leaves on trees and other plants change color and fall to the ground.

Amazing Fact!

Some squirrels store the nuts they collect by burying them underground. They sometimes forget where they buried the nuts. The nuts then grow into new trees!

During fall, animals begin to prepare for cold weather. Some animals begin to gather and store food. Some animals grow fur or seek shelter.

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Try This!

Do plants grow better when it is cold or when it is warm?

Plan and carry out an investigation to find out.

Describe the weather in winter. How is it different from the other seasons?

Winter

Winter is the coldest season. It is also the season with the fewest hours of daylight.

Many plants have lost their leaves. It may rain a lot. If the weather is cold enough, the ground may be covered in snow.

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During winter, there is not much food for animals to eat. Some animals seek shelter or move to warmer places.

What things do people do to stay warm in winter?

AB

Amazing Fact!

During winter, some animals seek shelter and enter into a deep sleep for many weeks. They awaken in spring when the temperature is warmer and food is available.

Activity 5.9

Go Online!

Watch the amazing transformations that take place from season to season on the NGScience website.

QuickCode: D6M2

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Day Length and Seasons How does the length of daylight change from season to season?

Try This!

How does the length of daylight change throughout the year in your area? As a class, plan and carry out an investigation to find out.

As the seasons change throughout the year, so too does the amount of sunlight. This causes changes in the length of day and night.

In summer, the Sun rises early in the morning and sets late in the evening.

Spring

Summer

Sunrise

Sunset

Daylight

Sunrise

Sunset

Daylight

7:15 a.m.

7:15 p.m.

12 hours

5:30 a.m.

8:30 p.m.

15 hours

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In spring and fall, the Sun rises later in the morning and sets earlier in the evening.

In winter, the Sun rises very late and sets very early. Compared to other seasons, the days are the shortest and nights are the longest.

Amazing Fact!

In the areas around the North Pole and South Pole, the Sun does not set during summer. They are in constant daylight!

How does the change in length of daylight affect the activities of people?

AB

Activity 5.10 Fall

Winter

Sunrise

Sunset

Daylight

Sunrise

Sunset

Daylight

6:45 a.m.

7:45 p.m.

13 hours

7:30 a.m.

6:30 p.m.

11 hours

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A Closer Look

Monsoons Not all places experience the four seasons of summer, fall, winter and spring. In some places, there are just two seasons – a dry season and a wet season. The wet season is also called a monsoon season.

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During a monsoon, the wind blows in the same direction and it rains a lot. The rain provides living things with the water they need.

If it rains heavily for a long time, water may cover parts of the land. This is called a flood.

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Science Words

weather wind storm temperature thermometer thunderstorm hurricane wildfire

drought flood seasons spring summer fall winter

Review

1. List four words you can use to describe the weather.

2.

What is temperature? (a) A tool used to measure weather. (b) How hot or cold the air outside is. (c) How strong the wind blows.

3. Which tool or instrument is used to measure temperature? (a) rain gauge (b) anemometer (c) thermometer

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4. Which tool or instrument is used to measure wind speed? (a) rain gauge (b) anemometer (c) thermometer 5. Use the words in the box to label the pictures. flood hurricane thunderstorm wildfire (a) (b)

(c) (d)

6. List the four seasons. Write a few words to describe the weather in each season.

7. Which season has the least hours of daylight?

8. Which season has the most hours of daylight?

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In the Field

When most people see severe weather, they stay well away.

A storm chaser is a scientist that does the opposite – they follow and observe severe weather as it moves!

Storm chasers use special instruments to learn about storms and other types of severe weather.

They observe weather patterns to learn how storms move and predict where and when a storm will form.

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Storm chasers communicate the patterns and behaviors of storms they observe. This helps people to prepare for and stay safe during severe weather.

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