1. End Show Slide 1 of 37 Copyright Pearson Prentice Hall Biology

2. End Show Slide 2 of 37 Copyright Pearson Prentice Hall 37-3 The Respiratory System

3. End Show 37-3 The Respiratory System Slide 3 of 37 Copyright Pearson Prentice Hall What Is Respiration? In biology, respiration means two different things. Cellular respiration is the release of energy from the breakdown of food in the presence of oxygen. At the organism level, respiration is the process of gas exchange—the release of carbon dioxide and the uptake of oxygen between the lungs and the environment.

4. End Show 37-3 The Respiratory System Slide 4 of 37 Copyright Pearson Prentice Hall The Human Respiratory System What is the function of the respiratory system?

5. End Show 37-3 The Respiratory System Slide 5 of 37 Copyright Pearson Prentice Hall The Human Respiratory System The basic function of the human respiratory system is the exchange of oxygen and carbon dioxide between the blood, the air, and tissues.

6. End Show 37-3 The Respiratory System Slide 6 of 37 Copyright Pearson Prentice Hall The Human Respiratory System The respiratory system consists of the: nose pharynx larynx trachea bronchi lungs

7. End Show 37-3 The Respiratory System Slide 7 of 37 Copyright Pearson Prentice Hall The Human Respiratory System Air entering the respiratory system must be warmed, moistened, and filtered. Mucus moistens air and traps particles of dust or smoke. Cilia sweep particles and mucus to the throat. Mucus and particles are either swallowed or spit out.

8. End Show 37-3 The Respiratory System Slide 8 of 37 Copyright Pearson Prentice Hall The Human Respiratory System Epiglottis Trachea Nose Pharynx Larynx Lungs Bronchus Mouth Diaphragm Bronchioles

9. End Show 37-3 The Respiratory System Slide 9 of 37 Copyright Pearson Prentice Hall The Human Respiratory System Air enters the nose or mouth and moves to the pharynx, or throat. The pharynx serves as a passageway for both air and food. Nose Pharynx

10. End Show 37-3 The Respiratory System Slide 10 of 37 Copyright Pearson Prentice Hall The Human Respiratory System Air moves from the pharynx into the trachea, or windpipe. The epiglottis covers the entrance to the trachea when you swallow. Epiglottis Trachea

11. End Show 37-3 The Respiratory System Slide 11 of 37 Copyright Pearson Prentice Hall The Human Respiratory System At the top of the trachea is the larynx, which contains two elastic folds of tissue called vocal cords. Larynx

12. End Show 37-3 The Respiratory System Slide 12 of 37 Copyright Pearson Prentice Hall The Human Respiratory System Air then passes through the trachea into two large passageways in the chest cavity called bronchi. Each bronchus leads into one of the lungs. Lungs Bronchus

13. End Show 37-3 The Respiratory System Slide 13 of 37 Copyright Pearson Prentice Hall The Human Respiratory System In each lung, the bronchus subdivides into smaller bronchi, and then into bronchioles. Bronchioles

14. End Show 37-3 The Respiratory System Slide 14 of 37 Copyright Pearson Prentice Hall The Human Respiratory System Bronchioles subdivide into millions of tiny air sacs called alveoli. Alveoli Bronchiole

15. End Show 37-3 The Respiratory System Slide 15 of 37 Copyright Pearson Prentice Hall The Human Respiratory System Alveoli are grouped in clusters. A network of capillaries surrounds each alveolus. Pulmonary vein Capillaries Pulmonary artery

16. End Show 37-3 The Respiratory System Slide 16 of 37 Copyright Pearson Prentice Hall Gas Exchange Gas exchange takes place in the alveoli. Oxygen diffuses into the blood. Capillary O2O2

17. End Show 37-3 The Respiratory System Slide 17 of 37 Copyright Pearson Prentice Hall Gas Exchange Carbon dioxide in the blood diffuses into the alveolus. Capillary O2O2 CO 2

18. End Show 37-3 The Respiratory System Slide 18 of 37 Copyright Pearson Prentice Hall Breathing Breathing is the movement of air into and out of the lungs. The force that drives air into the lungs comes from air pressure.

19. End Show 37-3 The Respiratory System Slide 19 of 37 Copyright Pearson Prentice Hall Breathing Lungs are sealed in pleural membranes inside the chest cavity. At the bottom of the cavity is a large, flat muscle known as the diaphragm.

20. End Show 37-3 The Respiratory System Slide 20 of 37 Copyright Pearson Prentice Hall Breathing During inhalation, the diaphragm contracts and the rib cage rises up. This expands the volume of the chest cavity.

21. End Show 37-3 The Respiratory System Slide 21 of 37 Copyright Pearson Prentice Hall Breathing The chest cavity is sealed, so this creates a partial vacuum inside the cavity. Atmospheric pressure fills the lungs as air rushes into the breathing passages.

22. End Show 37-3 The Respiratory System Slide 22 of 37 Copyright Pearson Prentice Hall Breathing Often exhaling is a passive event. When the rib cage lowers and the diaphragm relaxes, pressure in the chest cavity is greater than atmospheric pressure. Air is pushed out of the lungs. Exhalation Rib cage lowers Air Exhaled

23. End Show 37-3 The Respiratory System Slide 23 of 37 Copyright Pearson Prentice Hall How Breathing Is Controlled Breathing is controlled by the medulla oblongata. The medulla oblongata monitors carbon dioxide in the blood. As carbon dioxide increases, nerve impulses make the diaphragm contract, bringing air into the lungs. The higher the carbon dioxide level, the stronger the impulses.

24. End Show 37-3 The Respiratory System Slide 24 of 37 Copyright Pearson Prentice Hall Tobacco and the Respiratory System Tobacco smoke contains three dangerous substances that affect the body: nicotine carbon monoxide tar

25. End Show 37-3 The Respiratory System Slide 25 of 37 Copyright Pearson Prentice Hall Tobacco and the Respiratory System Nicotine is a stimulant that increases heart rate and blood pressure. Carbon monoxide is a poisonous gas that blocks the transport of oxygen by hemoglobin in the blood. Nicotine and carbon monoxide paralyze the cilia. Tar contains compounds that are known to cause cancer.

26. End Show 37-3 The Respiratory System Slide 26 of 37 Copyright Pearson Prentice Hall Tobacco and the Respiratory System Diseases Caused by Smoking How does smoking affect the respiratory system?

27. End Show 37-3 The Respiratory System Slide 27 of 37 Copyright Pearson Prentice Hall Tobacco and the Respiratory System Smoking reduces life expectancy. Smoking can cause such respiratory diseases as chronic bronchitis, emphysema, and lung cancer.

28. End Show 37-3 The Respiratory System Slide 28 of 37 Copyright Pearson Prentice Hall Tobacco and the Respiratory System In chronic bronchitis, the bronchi become swollen and clogged with mucus. Emphysema is the loss of elasticity in lung tissues. People with emphysema cannot get enough oxygen to the body tissues or rid the body of excess carbon dioxide.

29. End Show 37-3 The Respiratory System Slide 29 of 37 Copyright Pearson Prentice Hall Tobacco and the Respiratory System Smoking is a preventable cause of lung cancer. Lung cancer is deadly because its cells can spread to other locations. Smoking is also a major cause of heart disease.

30. End Show 37-3 The Respiratory System Slide 30 of 37 Copyright Pearson Prentice Hall Tobacco and the Respiratory System Smoking and the Nonsmoker Passive smoking is damaging to young children because their lungs are still developing. Studies show that children of smokers are twice as likely as children of nonsmokers to develop respiratory problems.

31. End Show 37-3 The Respiratory System Slide 31 of 37 Copyright Pearson Prentice Hall Tobacco and the Respiratory System Dealing With Tobacco The best way to avoid tobacco-related illness is not to smoke. If a smoker quits, his or her health can be improved, and some of the damage can be reversed.

32. End Show - or - Continue to: Click to Launch: Slide 32 of 37 Copyright Pearson Prentice Hall 37-3

33. End Show Slide 33 of 37 Copyright Pearson Prentice Hall 37-3 Air passes through the trachea into two large passageways in the chest cavity known as the a.bronchi. b.alveoli. c.epiglottis. d.bronchioles.

34. End Show Slide 34 of 37 Copyright Pearson Prentice Hall 37-3 The function of the cilia lining the respiratory surfaces is to a.improve the amount of oxygen and carbon dioxide exchanged in the lungs. b.cover the opening of the trachea when you swallow. c.move air in and out of the lungs. d.sweep trapped particles and mucus away from the lungs.

35. End Show Slide 35 of 37 Copyright Pearson Prentice Hall 37-3 Oxygen diffuses from the alveolus into the blood because a.blood entering the capillaries of the lungs is oxygen-poor. b.blood entering the capillaries of the lungs is oxygen-rich. c.air entering the lungs has more carbon dioxide than oxygen. d.air entering the lungs has less oxygen than is found in the blood.

36. End Show Slide 36 of 37 Copyright Pearson Prentice Hall 37-3 A stimulant drug found in tobacco that increases the heart rate and blood pressure is a.tar. b.carbon monoxide. c.nicotine. d.carbon dioxide.

37. End Show Slide 37 of 37 Copyright Pearson Prentice Hall 37-3 A respiratory disease that results in the loss of elasticity in the tissues of the lung is a.chronic bronchitis. b.lung cancer. c.emphysema. d.pneumonia.

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