Which of the following is a pressure wave created by the expansion and recoiling of arteries?

1. Which of the following is a pressure wave created by the expansion and recoiling of arteries? • A) Circulation • B) Pulse • C) Blood flow • D) Blood pressure

2. Respiration & Immunity Chs 14 & 13

3. Outline • Respiration • Overview- structure and function • The Lungs & gas exchange • The throat • Breathing mechanisms • Transport and management of gases • Control of breathing • Disorders of the respiratory sytem

4. Communication and gas exchange are the primary purposes of the respiratory system • In the respiratory system, oxygen and carbon dioxide are exchanged across a moist body surface • Pressure changes within the lungs cause breathing • Blood transports gases between the lungs and the cells • Breathing is controlled primarily by respiratory centers in the brain • Respiratory disorders have many causes

5. Gas exchange at the organismal level, called, external respiration, is necessitated by gas exchange at the cellular level, called internal respiration Breathing moves airin and out of the lungs. External respirationis the exchange ofoxygen and carbondioxide between thelungs and the blood. Gas transportmoves oxygen andcarbon dioxidebetween the lungsand the body tissues. Internal respiration isthe exchange of oxygenand carbon dioxidebetween blood and thebody tissues. Oxygentransport Carbondioxidetransport Lungs Tissue Gas diffusion Gas diffusion Figure 14.1

6. Structures of the Respiratory System UPPER RESPIRATORYSYSTEM Sinuses • Cavities in skull • Lighten head • Warm and moistenair • Filters, warms, andmoistens air Nasal cavity • Produces mucus • Filters, warms, andmoistens air • Olfaction Pharynx • Passageway forair and food RESPIRATORYMUSCLES • Cause breathing Intercostalmuscles Diaphragm • Muscle sheet betweenchest and abdominalcavities with a role inbreathing • Move ribs during breathing Figure 14.2 (1 of 2)

7. The Lower Respiratory System LOWER RESPIRATORYSYSTEM• Exchanges gases Epiglottis • Covers larynx duringswallowing Larynx •Air passageway • Prevents food and drinkfrom entering lowerrespiratory system • Produces voice Lungs • Structures that containalveoli and airpassageways • Allow exchange ofoxygen and carbondioxide betweenatmosphere and blood Bronchi • Two branches oftrachea that conductair from trachea toeach lung Trachea • Connects larynx withbronchi leading toeach lung • Conducts air to andfrom bronchi Bronchioles • Narrow passagewaysto conduct air frombronchi to alveoli Alveoli • Microscopic chambersfor gas exchange Figure 14.2 (2 of 2)

8. The Respiratory System • The nose • Cleans incoming air • Warms and moistens the air • Provides for the sense of smell

9. Figure 14.4a

10. The Respiratory System • The sinuses • Lighten the head • Adjust air quality • The pharynx • The space behind the nose and mouth • Provides a passageway for food and air

11. The Respiratory System • The larynx • An adjustable entrance to the respiratory system • Controls the position of the epiglottis to prevent materials from entering the lower respiratory system • The source of the voice

12. The Respiratory System Epiglottis Larynx Uppertrachea Front view (a) The epiglottis is open during breathing but covers theopening to the larynx during swallowing to preventfood or drink from entering the trachea. Figure 14.5a

13. The Respiratory System Vocal cords Glottis Top view of larynx Top view of larynx During quiet breathing, thevocal cords are near thesides of the larynx, and theglottis is open. During speech, the vocalcords are stretched over theglottis and vibrate as airpasses through them,producing the voice. (b) The vocal cords are the folds of connective tissue above theopening of the larynx (the glottis) that produce the voice. Figure 14.5b

14. The Respiratory System • The trachea • Tube that conducts air between the environment and the lungs • Heimlich maneuver • Can be used to dislodge food from the trachea

15. The Heimlich maneuver is only a last resort A person who is choking cannot speakor breathe and needs immediate help.The Heimlich maneuver is aprocedure intended to force a largeburst of air out of the lungs anddislodge the object blocking air flow. Step 1: Stand behind the chokingperson with arms around the waist. Step 2: Make a fist and place thethumb of the fist beneath thevictim’s rib cage about midwaybetween the navel (belly button) andthe breastbone. Figure 14.6 (1 of 2)

16. The Heimlich maneuver saves lives, but also breaks ribs- try a whack on the back first Step 3: Grasp the fist with yourother hand and deliver a rapid “bearhug” up and under the rib cage withthe clenched fist. Be careful not topress on the ribs or the breastbonebecause doing so could causeserious injury. Blockingobject Step 4: Repeat until the objectis dislodged. Figure 14.6 (2 of 2)

17. The Respiratory System • The trachea divides into the bronchial tree which conducts air to each lung

18. The trachea branches off into bronchioles, which terminate in the alveoli Figure 14.7

19. The Respiratory System • The alveoli • Functional units of the respiratory system • Minute sacs where oxygen diffuses from the air into the blood • For alveoli to function properly they are coated with phospholipid molecules called surfactant that keep them open

20. The Respiratory System Figure 14.8

21. The Respiratory System • Carbon dioxide produced by the cells diffuses from the blood into the alveolar air to be exhaled

22. Which of the following is a thin-walled, rounded chamber surrounded by a vast network of capillaries? • A) Surfactant • B) Alveolus • C) Diaphragm • D) Glottis

23. Pressure Changes within the Lungs Cause Breathing • Pressure changes within the lungs cause breathing

24. Pressure Changes within the Lungs Cause Breathing • When the diaphragm and intercostal muscles contract, the volume of the thoracic cavity increases, causing the pressure in the lungs to decrease

25. Pressure Changes within the Lungs Cause Breathing • Expiration • When the same muscles relax, pressure in the lungs increase • Inspiration • Occurs when the pressure in the lungs decreases

26. Lungs contain no muscle tissue Inhalation Air flow Rib cagemoves upand out Intercostalmusclescontract Diaphragmcontractsand flattens Diaphragmcontracts The chest cavity increasesin size, and pressure withinthe lungs decreases. The lungs expand, andair moves in. (a) Figure 14.9a

27. The diaphragm and intercostal muscles fill and empty the lungs by changing pressure in the pleural cavity Exhalation Air flow Rib cagemoves downand inward Intercostalmuscles relax Diaphragmrelaxes andmoves upward Diaphragmrelaxes The chest cavity decreasesin size, and pressurewithin the lungs increases. The lungs recoil,and air moves out. (b) Figure 14.9b

28. Lung volumes are dependent on energy expenditure and the need for residual air to prevent collapse of the lungs • The volume of air inhaled or exhaled during a normal breath is called the tidal volume • The volume of air moved into and out of the lungs is an indication of health

29. Pressure Changes within the Lungs Cause Breathing 6000 Inspiratoryreserve(forcedinhalation)volume Totallungcapacity 5000 Vitalcapacity 4000 Tidal volume Lung Volume (ml) 3000 Expiratory reserve(forced exhalation)volume 2000 1000 Residualvolume 0 Figure 14.10 (1 of 2)

30. Pressure Changes within the Lungs Cause Breathing Tidal volume(~500 ml) Amount of air inhaled or exhaledduring an ordinary breath Amount of air that can be inhaledin addition to a normal breath Inspiratory reserve volume(~1900–3300 ml) Expiratory reserve volume(~1000 ml) Amount of air that can be exhaledin addition to a normal breath Vital capacity(~3400–4800 ml) Maximum amount of air that canbe inhaled or exhaled in a singleforced breath Residual volume(~1100–1200 ml) Amount of air remaining in thelungs after maximum exhalation Total lung capacity(4500–6000 ml) Total amount of air in the lungsafter maximal inhalation (vitalcapacity + residual volume) Figure 14.10 (2 of 2)

31. Blood Transports Gasses between the Lungs and the Cells • Most oxygen is carried by the blood where it is bound to hemoglobin in a molecule called oxyhemoglobin • The carbon dioxide produced as the cells use oxygen is removed by the blood in one of three ways • Dissolved in the blood • Carried by hemoglobin • As a bicarbonate ion

32. In the lungs, O2 passes in to the bloodstream, and CO2 passes out to the lungs Figure 14.11 (2 of 2)

33. By what process does O2 enter the capillaries of the lungs? • Active transport • Osmosis • Simple diffusion • Facilitated diffusion

34. By what process does CO2 leave the capillaries for the lungs? • Active transport • Osmosis • Simple diffusion • Facilitated diffusion

35. In the body, CO2 leaves cells into the blood Figure 14.11 (1 of 2)

36. Gas exchange affects blood pH • CO2 dissolved in the blood affects its pH • CO2 +H2O H+ + HCO3-

37. CO2 +H2O H+ + HCO3-according to the equation, CO2in the blood acts as a • Acid • Base

38. Blood Transports Gasses between the Lungs and the Cells • CO2 dissolved in the blood affects its pH • CO2 +H2O H+ + HCO3- • This chemical reaction can also go backward, or further forward • HCO3- H+ + CO32- • When sodium from the diet is added, much bicarbonate ion that also serves as a buffer • In the lungs, removal of CO2 causes removal of H+ from the bloodstream

39. Blood Transports Gasses between the Lungs and the Cells • CO2 dissolved in the blood affects its pH • CO2 +H2O H+ + HCO3- • This chemical reaction can also go backward • When sodium from the diet is added, much bicarbonate ion that also serves as a buffer • In the lungs, removal of CO2 causes removal of H+ from the bloodstream

40. Breathing Is Controlled by Respiratory Centers in the Brain • The basic rhythm of breathing • Controlled by a breathing center located in the medulla

41. Breathing Is Controlled by Respiratory Centers in the Brain Figure 14.12 (1 of 2)

42. Breathing Is Controlled by Respiratory Centers in the Brain Figure 14.12 (2 of 2)

43. Respiratory Centers in the Brain • Changes in depth and rate of breathing • Affected by chemoreceptors located in the medulla

44. Respiratory Centers in the Brain • Carbon dioxide • The most important chemical influencing breathing rate

45. Respiratory Centers in the Brain Increased blood level of carbondioxide (increased acidity, H+) Increased carbon dioxide level(increased acidity, H+) incerebrospinal fluid Sensed by chemoreceptorsin medulla Sensed by peripheralchemoreceptors in aortic andcarotid bodies Medulla breathing centerstimulated Breathing rate increased(more carbon dioxideexhaled) Carbon dioxidelevel in bloodreturns to normal Figure 14.13

46. Respiratory Centers in the Brain • Under extreme circumstances, oxygen-sensitive chemoreceptors in the aortic and carotid bodies can increase breathing

47. Respiratory Disorders Have Many Causes • The common cold • Caused by several types of viruses • Some with many variants

48. Respiratory Disorders Have Many Causes • Influenza • Caused by only two types of viruses • There are many variants of these two types

49. Respiratory Disorders Have Many Causes • Pneumonia • An inflammation of the lungs that causes fluid to accumulate in the alveoli, reducing gas exchange

50. Respiratory Disorders Have Many Causes • Strep throat • Caused by Streptococcus bacteria • Soreness accompanied by swollen glands and fever