1. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
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2. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
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3. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Strong Bones
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4. Strong Bones Bones, ligaments, and cartilage form the skeletal system.
Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Strong Bones
Bones, ligaments, and cartilage form the skeletal system.
Bones are organs that support and protect the body, store minerals, and allow movement.
Bones have a hard outer layer that contains calcium and a spongy inner layer called marrow where blood cells are made.
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5. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Strong Bones
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6. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Strong Bones
Cartilage cushions the ends of bones and forms flexible parts such as your ears and nose.
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7. Strong Bones Ligaments connect bones at joints.
Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Strong Bones
Ligaments connect bones at joints.
The place where two or more bones meet is called a joint.
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8. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Strong Bones
Some joints, like those in the skull, don’t move. Other joints allow movement.
Ball-and-Socket Joints allow circular movement, like the joint in your shoulder.
Hinge Joints allow back-and-forth movement, like the hinge in your knee.
Pivot Joints allow rotation from side to side, like the joint in your neck.
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9. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Strong Bones
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10. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Mighty Muscles
Muscles are organs that contract to produce movement in the body.
There are three types of muscles in the muscular system.
The heart is made of one type.
The walls of blood vessels and organs are made of another type of muscle.
A third type, the skeletal muscle, pulls bones to help us move.
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11. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Mighty Muscles
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12. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Mighty Muscles
Tendons are strong bands of tissues that connect skeletal muscles to bones.
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13. Mighty Muscles Muscle movement can be involuntary or voluntary.
Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Mighty Muscles
Muscle movement can be involuntary or voluntary.
Involuntary movements happen without thinking about them, like your heart beating.
Voluntary movements can be controlled, such as running and playing.
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14. Mighty Muscles Muscles often work in pairs.
Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Mighty Muscles
Muscles often work in pairs.
When one muscle contracts, the other muscle in the pair relaxes.
The contracting muscle moves the bone that it’s attached to.
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15. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Mighty Muscles
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16. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Breathe In, Breathe Out
Organs in the respiratory system bring in oxygen and release carbon dioxide.
Lungs, the main organs of the respiratory system, are spongy organs that expand to fill with air.
Air enters the body through the nose or mouth and flows through a tube in the throat called the trachea.
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17. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Breathe In, Breathe Out
1200,28000,28000
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18. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Breathe In, Breathe Out
The trachea branches into two smaller tubes called bronchi.
Bronchi branch into many bronchioles in the lungs.
Tiny sacs called alveoli are attached to bronchioles. Red blood cells in the alveoli absorb oxygen.
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19. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Breathe In, Breathe Out
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20. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Breathe In, Breathe Out
They inflate and deflate as you inhale and exhale.
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21. Breathe In, Breathe Out Word Bank Alveoli Bronchi Bronchioles Trachea
Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Breathe In, Breathe Out
Word Bank
Alveoli
Bronchi
Bronchioles
Trachea
Carbon dioxide
Oxygen
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22. Asthma Attack Constricted Airways
Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Asthma Attack
Constricted Airways
Asthma is an illness that makes it hard for a person to breathe.
During an asthma attack, bronchi become swollen, making airways smaller. This makes it much harder to get air in and out of the lungs.
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23. Asthma Attack Constricted Airways
Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Asthma Attack
Constricted Airways
swollen- - breathe
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24. Asthma Attack Triggers The exact causes of asthma aren’t known.
Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Asthma Attack
Triggers
The exact causes of asthma aren’t known.
Some people are born with asthma, while for other people, smoke, air pollution, and allergies can trigger an asthma attack.
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25. Asthma Attack Management
Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Asthma Attack
Management
People can try to avoid asthma triggers; however, people can’t always avoid pollen or air pollution.
A doctor can prescribe an inhaler, a device that delivers medication to the lungs. The inhaler releases a mist that can help open up airways.
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26. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Beat It
The heart, vessels, and blood are all part of the circulatory system.
The heart is a muscular organ that pumps blood throughout the body. It contracts in two phases.
When the top part relaxes, it fills with blood. When it contracts, the top part squeezes blood to the lower part.
When the lower part contracts, it squeezes blood from the heart into vessels and all parts of the body.
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27. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Beat It
Blood is made up of a clear liquid called plasma and small structures called blood cells.
Red blood cells carry oxygen throughout the body.
White blood cells help fight disease.
Platelets stop bleeding by forming clots.
Plasma carries nutrients throughout the body.
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28. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Beat It
Arteries carry blood away from the heart. Veins bring blood back to the heart from the lungs and the body.
Oxygen, nutrients, and carbon dioxide pass through capillaries, or tiny vessels with very thin walls, to parts of the body and into the blood.
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29. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
Beat It
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30. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
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31. Unit 3 Lesson 4 How Do Our Bodies Move, Breathe, and Circulate Blood?
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