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1 2 3 4 5 6 7 8 9 10 021 13 12 11 10 09 08 Lesson 1 • Your Body .2 Explore Activity: How are faces alike and different? .3 History of Science: Discovering X-rays. 10 Lesson 2 • Bones and Muscles. 12 Explore Activity: How can you pick up things?. 13 Lesson 3 • Heart and Lungs.
20 Explore Activity: What is your pulse?. 21 Lesson 4 • Your Stomach .28 Explore Activity: How does your mouth change the food you eat?. 29 Animal Bodies: The Cow Stomach. 36 Lesson 5 • Your Senses .38 Explore Activity: What is in the bag?.
39 Science, Technology, and Society: Hearing Aids. 46 Lesson 6 • Growing and Changing. 48 Explore Activity: How have you changed?. 49 Animal Bodies: Long Lives, Short Lives.
56 Lesson 7 • Eating Healthful Foods .58 Explore Activity: What makes a healthful meal?. 66 Lesson 8 • Staying Healthy and Safe. 68 Explore Activity: What things help keep you healthy or safe?. 76 iii Lesson 1 Your Body How are all these children alike? How are they different? 2 ENGAGE How are faces alike and You need different? What to Do Observe.
Work with two classmates. Look closely at their faces. crayons Record Data. Draw a picture of their faces.
Share your drawings with the group. Discuss how their faces are alike and different. paper Explore More Step Communicate. Find photographs of people in books or magazines.
How do their faces compare with yours? 3 EXPLORE What parts make up the body? The body needs many things Vocabulary to stay alive. It needs food, system water, and air. The body also must get rid of wastes. Wastes are things the body makes but does not need.
Many parts make up the body. There are parts on the outside and the inside. All body parts work together to keep you alive and healthy. They help the body get what it needs.
▲ The body and a toy What body parts are you using clock are made of right now? parts that work together. 4 EXPLAIN Body Parts head brain chest lung heart stomach arm intestine bone hand finger leg muscle foot Read a Diagram What body parts are in the chest? 5 EXPLAIN Body Systems Each body part does a different job. Some parts work only when they are needed. Other parts work all the time.
A system is a group of parts that work together. The body uses many systems to meet its needs. moving keeping warm eating and drinking 6 EXPLAIN The nose and lungs work in a body system that takes in air. The teeth and stomach work Classify.
List three in a system that takes in food. things you did Bones and muscles work in today. Which body systems too. parts helped you do them? What do body systems do? You use many body systems every day.
▼ breathing 7 EXPLAIN One of a Kind Everyone uses the same kinds of body systems and the same kinds of parts. But people are different from one another too. Everyone is one of a kind! Bodies come in different colors, sizes, and shapes. People also think, act, and feel in many ways.
How are you one of a kind? ▼ Everyone is one of a kind. 8 EXPLAIN Complete each sentence. Your body is made of many system. A group of body parts that works together is a.
Answer the questions below. What is one way that body parts work together? 4. What is one way that all people are alike? What is one way they can be different? Think of three ways that you used your body today. Draw pictures to show each way.
9 EVALUATE Discovering X-rays In 1895 Wilhelm Roentgen hands discovered the X-ray. The ray passed through skin and other soft things. It did not pass through bone. spine Today doctors know how to read an X-ray picture of the human body.
X-rays can show damage to bones, lungs, and other inside body parts. 10 EXTEND History of Science In 1974 the MRI camera was invented. It can show better pictures of your heart, brain, and lungs. An MRI took this picture of a human brain.
MRI picture ultrasound picture One tool uses sounds to take pictures. Sounds made this picture of a baby inside the mother. *6A@j 7DJIj I How do X-rays help doctors? 11 EXTEND Lesson 2 Bones and Muscles What can you do with your arms and hands? 12 ENGAGE How can you pick up You need things? What to Do Choose places along your arm. Try to pick up a ball at each place.
Do not use tennis ball other body parts. Draw a picture of your arm. Step Label the places that could pick up the ball. How are the places that could Step pick up the ball alike? Explore More Make a model.
How could you build a model of your arm? Discuss your ideas. 13 EXPLORE How does the body move? Bones are hard parts inside the body. All together bones Vocabulary make up the skeleton. The skeleton skeleton allows the body to joint stand and move.
muscle skull jaw ribs arm bones Bones come in different shapes spine and sizes. When children grow, their bones grow longer and wider. ▶ leg bones 14 EXPLAIN Bones also protect the soft parts of the body. Rib bones in the chest protect the heart and lungs.
The skull protects the brain. Bones meet at joints. Joints allow body parts to bend, turn, or twist. Together the joints let the body move in many ways.
How do bones help the body? Two Joints of the Arm shoulder joint elbow joint Read a Diagram How are joints alike? How are they different? 15 EXPLAIN Muscles Bones do not move by themselves. Muscles move the skeleton and other body parts. A muscle can tighten or relax. Many muscles pull on bones to make them move.
Muscles inside the face pull on skin. You use more muscles to frown than you use to smile! ▶ 16 EXPLAIN Muscles can pull, but they can not push. Most muscles work in pairs. If one muscle pulls a Compare.
How is bone up, a second muscle the thumb different pulls it back down. from other fingers? Compare how they How do muscles move bones? bend and move. ◀ Two muscles work together to move the elbow. One muscle tightens, or pulls.
The other muscle relaxes. 17 EXPLAIN Types of Muscle The body uses three types of muscle. They are skeletal, heart, and smooth muscle. You can control only skeletal muscle.
Other muscles work ▲ Exercising every day without you ever thinking helps keep all of your about them. bones and muscles strong. What are the three types of muscle? What do they do? Three Types of Muscle Skeletal muscle Heart muscle Smooth muscle moves bones. pumps blood moves the stomach through the and other soft heart.
18 EXPLAIN Complete each sentence. All of the bones inside the muscles body make up the. Body parts that move bones are called. Two bones meet at a.
Answer the question below. Name three places in the body where you can find muscles. Choose a joint in the body. Draw a picture that shows how it moves.
19 EVALUATE Lesson 3 Heart and Lungs What body parts work harder when you play? 20 ENGAGE What is your pulse? You need What to Do Use one finger to feel the side of your neck. Feel for a beating just below the skin. This beating is called stop the pulse. watch Press the clay on this spot.
Carefully push one end of the straw into the clay. clay The other end should stick out straight. thin straw Measure. Have your Step partner count the number of times the straw moves in one minute.
Explore More Compare. Run in place for 30 seconds. Then repeat the activity. How did your pulse change? 21 EXPLORE What do your heart and lungs do? Blood brings food, water, and Vocabulary oxygen to every body part.
It heart also carries away wastes. The artery heart and lungs work together vein to help blood do this. lungs diaphragm The heart pumps blood through the body. Its walls are made of thick muscle.
Pumping Blood to body from body to lungs from lungs The heart pumps from lungs blood in a cycle called a heart beat. The arrows show the direction that blood flows. ▶ from body to body 22 EXPLAIN The heart contracts, or squeezes, blood out through tubes called arteries. Blood returns to the heart through tubes called veins.
heart An artery moves or beats when blood rushes through it. This beating is called the pulse. The pulse tells how fast or slow the heart is beating. What job does the heart do? veins arteries Arteries carry blood with oxygen to every body part.
Then veins carry away blood with wastes. ▶ 23 EXPLAIN Breathing Breathing brings air into the body. Then blood gets oxygen from air. Breathing also removes a waste gas called carbon dioxide.
When you breathe, air enters the body through the nose or mouth. Tubes carry air from the throat to the lungs. The lungs are where air enters the blood. A System for Breathing nose mouth air tubes lungs Read a Diagram How does air enter and leave the lungs? 24 EXPLAIN The lungs can not move by themselves.
A muscle called the diaphragm works to fill Observe. Hold a and empty them. piece of paper in front of your mouth. What do the lungs do? Observe the paper as you breathe in and breathe out.
The Diaphragm at Work Air moves into your lungs through your nose or mouth. The ribs move up and out. The chest and lungs get larger. The diaphragm moves down and flattens.
Air rushes into the lungs. 25 EXPLAIN Working Hard Your heart and lungs work all the time. They work even when you are sleeping. You breathe faster when you exercise.
Your heart beats faster too. This helps bring more food and oxygen to the muscles. When do the heart and lungs work their hardest? When you exercise, your body needs more oxygen.▼ 26 EXPLAIN Complete each sentence. A muscle called the heart pumps blood through the lungs body.
Tubes called carry blood with oxygen to body parts. Air meets blood in the. Answer the question below. How is the heart different from other muscles of the body? Draw a picture of yourself when your heart and lungs are working very hard.
27 EVALUATE Lesson 4 Your Stomach What happens to the food you eat? 28 ENGAGE How does your mouth You need change the food you eat? What to Do Put one cracker in a cup. Break the other cracker into pieces. two saltine Place the pieces in the crackers second cup. Add water and mash the pieces with a spoon.
How are the crackers in the cups the two small same? How are they cups different? Infer. How does your mouth change the food you eat? water Explore More Wet and mash other foods. Try a slice of apple or cheese. spoon 29 EXPLORE How does the body digest food? Food is fuel for the body.
The Vocabulary body must digest food to get digest energy from it.