1. Chapter 38 Table of Contents Section 1 The Circulatory System
Circulatory and Respiratory Systems
Chapter 38
Table of Contents
Section 1 The Circulatory System
Section 2 The Heart
Section 3 The Respiratory System

2. Section 1 The Circulatory System
Chapter 38
Objectives
List five types of molecules that are transported by the cardiovascular system.
Differentiate between arteries, capillaries, and veins.
Relate the function of the lymphatic system to the functions of the cardiovascular and immune systems.
Relate each component of blood to its function.
Summarize how a person’s blood type is determined.

3. Transport and Distribution
Section 1 The Circulatory System
Chapter 38
Transport and Distribution
The human cardiovascular system functions like a network of highways.
The circulatory system, which includes the cardiovascular and lymphatic systems, transports nutrients, hormones, and metabolic wastes to different parts of the body.
The respiratory system takes in oxygen, O2, and releases carbon dioxide, CO2.

4. Cardiovascular System
Section 1 The Circulatory System
Chapter 38
Cardiovascular System

5. Section 1 The Circulatory System
Chapter 38
Blood Vessels
Blood circulates through the body through a network of vessels.
Arteries are blood vessels that carry blood away from the heart.
Veins are blood vessels that carry the blood back to the heart.
Capillaries are tiny blood vessels that allow the exchange of gases, nutrients, hormones, and other molecules in the blood.

6. Section 1 The Circulatory System
Chapter 38
Blood Vessels

7. Blood Vessels, continued
Section 1 The Circulatory System
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Blood Vessels, continued
Arteries
Arteries have thick, elastic walls that can withstand the heart’s forceful pumping of blood. An artery’s wall expands when blood in pumped into it and then returns to its original size.

8. Blood Vessels, continued
Section 1 The Circulatory System
Chapter 38
Blood Vessels, continued
Capillaries
No cell in the human body is more than a few cell diameters away from a capillary.
Capillary walls are only one cell thick. Gas and nutrient molecules pass easily through their thin walls.

9. Blood Vessels, continued
Section 1 The Circulatory System
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Blood Vessels, continued
Veins
The walls of veins are much thinner than the walls of arteries. Veins are farther from the heart and exposed to lower pressures. Veins are larger in diameter than arteries.
Most veins have one-way valves. A valve is a flap of tissue that ensures that blood that passes through does not flow backwards.

10. Blood Vessels, continued
Section 1 The Circulatory System
Chapter 38
Blood Vessels, continued
Lymphatic System
The lymphatic system collects and recycles fluids leaked from the cardiovascular system. It is involved in fighting infections.
The lymphatic system is made up of a network of vessels called lymphatic vessels and tiny bean-shaped structures called lymph nodes. Lymph nodes may become swollen when they are fighting infection.

11. Section 1 The Circulatory System
Chapter 38
Movement of Lymph

12. Chapter 38 Components of Blood
Section 1 The Circulatory System
Chapter 38
Components of Blood
Blood contains water, a variety of molecules dissolved or suspended in the water, and three kinds of cells.

13. Components of Blood, continued
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Components of Blood, continued
Plasma
Plasma is the liquid portion of blood. It contains water and solutes, including metabolites and wastes, salts, and proteins.
Some plasma proteins enable blood clots to form. Other plasma proteins are antibodies that help the body fight disease.

14. Components of Blood, continued
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Components of Blood, continued
Blood Cells and Cell Fragments
Red blood cells carry oxygen. Anemia is a condition in which the oxygen-carrying capacity of the blood is reduced.
White blood cells defend the body against disease.
Platelets are cell fragments that play an important role in blood clotting.

15. Blood Clotting Cascade
Section 1 The Circulatory System
Chapter 38
Blood Clotting Cascade

16. Section 1 The Circulatory System
Chapter 38
Anemia

17. Components of Blood, continued
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Components of Blood, continued
Blood Type
The ABO blood group system is used to determine blood type. Under this system, the primary blood types are A, B, AB, and O. The letters A and B refer to antigens on the surface of red blood cells.
Blood transfusion recipients must receive blood that is compatible with their own blood type.

18. Components of Blood, continued
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Components of Blood, continued
Rh Factor
Rh factor is another important antigen on the surface of red blood cells. Persons who have this protein are Rh+. Persons who lack it are Rh-.

19. Section 1 The Circulatory System
Chapter 38
Blood and Blood Type

20. Chapter 38
Section 2 The Heart
Objectives
Differentiate the pulmonary circulation loop from the systemic circulation loop.
Summarize the path that blood follows through the heart.
Name the cluster of heart cells that initiates contraction of the heart.
Describe three ways to monitor the health of the circulatory system.
Name two vascular diseases, and identify factors that contribute to their development.

21. Chapter 38 A Muscular Pump
Section 2 The Heart
A Muscular Pump
The pumping action of the heart provides enough pressure to move blood throughout the body.
The heart is made up mostly of cardiac muscle tissue, which contracts to pump blood.

22. A Muscular Pump, continued
Chapter 38
Section 2 The Heart
A Muscular Pump, continued
Two Separate Circulatory Loops
The right side of the heart drives the pulmonary circulation loop, which pumps oxygen-poor blood to the lungs.
The left side of the heart drives the systemic circulation loop, which pumps oxygen-rich blood to the tissues of the body.

23. Circulatory Loops in the Human Body
Chapter 38
Section 2 The Heart
Circulatory Loops in the Human Body

24. Chapter 38
Section 2 The Heart
Systemic Circulation

25. Chapter 38 Circulation of Blood
Section 2 The Heart
Circulation of Blood
The left and right atria are chambers that receive blood returning to the heart. Below the atria are the left and right ventricles, thick-walled chambers that pump blood away from the heart.
The inferior vena cava and superior vena cava deliver blood directly into the right atrium of the heart. The aorta is a large artery that carries blood away from the heart. The coronary arteries supply the heart with oxygen-rich blood.

26. Path of Blood Flow Through the Heart
Chapter 38
Section 2 The Heart
Path of Blood Flow Through the Heart

27. Circulation of Blood, continued
Chapter 38
Section 2 The Heart
Circulation of Blood, continued
Initiating Contraction
Contraction of the heart is initiated by a small cluster of cardiac muscle cells called the sinoatrial node.
The sinoatrial node is embedded in the upper wall of the right atrium. The SA node is influenced by many factors, including hormones, temperature, and exercise.

28. Electrical Regulation of the Heart
Chapter 38
Section 2 The Heart
Electrical Regulation of the Heart

29. Circulation of Blood, continued
Chapter 38
Section 2 The Heart
Circulation of Blood, continued
Monitoring the Cardiovascular System
Blood pressure is the force exerted by blood as it moves through blood vessels. The pulse is a series of pressure waves within an artery caused by the contractions of the left ventricle.
A heart attack occurs when an area of the heart muscle stops working and dies. When an area of the brain dies the result is a stroke.

30. Chapter 38
Section 2 The Heart
Electrocardiogram

31. Chapter 38
Section 2 The Heart
Heart Attack

32. Chapter 38
Section 2 The Heart
Stroke

33. Section 3 The Respiratory System
Chapter 38
Objectives
Summarize the path that air follows when it enters the body through the nose or mouth.
Describe the role of the rib muscles and diaphragm in breathing.
Describe how breathing rate is regulated.
Summarize how oxygen and carbon dioxide are transported in the blood.
Identify three serious diseases of the lungs.

34. Section 3 The Respiratory System
Chapter 38
Gas Exchange
During aerobic respiration, cells must take in oxygen to oxidize glucose and make ATP.
Cells must also release carbon dioxide, a waste product of aerobic respiration.

35. Gas Exchange, continued
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Gas Exchange, continued
The Path of Air
From the nose, air passes through a muscular tube in the upper throat called the pharynx. The air flows through a passageway for air called the larynx.
Air then passes into the trachea. The trachea divides into two smaller tubes, the bronchi, which lead to the lungs. Within the lungs, gas exchange occurs in clusters of tiny sacs called alveoli.

36. The Human Respiratory System
Section 3 The Respiratory System
Chapter 38
The Human Respiratory System

37. Gas Exchange, continued
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Gas Exchange, continued
Lungs
The lungs are suspended in the chest cavity, bounded on the sides by the ribs and on the bottom by the diaphragm. The diaphragm is a muscle spanning the rib cage under the lungs.

38. Parts of the Human Respiratory System
Section 3 The Respiratory System
Chapter 38
Parts of the Human Respiratory System

39. Trachea, Bronchi, and Bronchioles
Section 3 The Respiratory System
Chapter 38
Trachea, Bronchi, and Bronchioles

40. Section 3 The Respiratory System
Chapter 38
Alveolus/Alveoli

41. Section 3 The Respiratory System
Chapter 38
Breathing
Air is drawn into and pushed out of the lungs by the mechanical process known as breathing.
When the diaphragm contracts, it moves down and air rushes into the lungs. When the diaphragm relaxes, it moves up and air is forced out.

42. Inhalation and Exhalation
Section 3 The Respiratory System
Chapter 38
Inhalation and Exhalation

43. Chapter 38 Breathing, continued Breathing Rate
Section 3 The Respiratory System
Chapter 38
Breathing, continued
Breathing Rate
Receptors in the brain and cardiovascular system continually monitor the levels of oxygen and carbon dioxide in the blood. The receptors send nerve signals to the brain.
The brain responds by sending signals to the diaphragm to speed or slow the rate of breathing.

44. Section 3 The Respiratory System
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Respiration

45. Gas Exchange in the Lungs
Section 3 The Respiratory System
Chapter 38
Gas Exchange in the Lungs

46. Section 3 The Respiratory System
Chapter 38
Gas Transport
After oxygen molecules enter the alveoli, they are picked up by red blood cells containing hemoglobin.

47. Gas Transport, continued
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Gas Transport, continued
Oxygen Transport
In the lungs, hemoglobin molecules in the blood pick up oxygen. The blood travels to the heart, then to the rest of the body.
In body tissues, oxygen diffuses into the cells for use during aerobic respiration. Carbon dioxide diffuses from the cells into the blood. In the lungs, carbon dioxide is released.

48. Hemoglobin and the Transport of Oxygen
Section 3 The Respiratory System
Chapter 38
Hemoglobin and the Transport of Oxygen

49. Gas Transport, continued
Section 3 The Respiratory System
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Gas Transport, continued
Carbon Dioxide Transport
Carbon dioxide, CO2, is carried by the blood in three forms: dissolved in blood plasma, attached to hemoglobin molecules, or as bicarbonate ions.
The CO2 ultimately diffuses out of the capillaries into the alveoli and is exhaled into the atmosphere.

50. Blood and the Transport of Carbon Dioxide
Section 3 The Respiratory System
Chapter 38
Blood and the Transport of Carbon Dioxide

51. Section 3 The Respiratory System
Chapter 38
O2 and CO2 in the Blood

52. Chapter 38 Respiratory Diseases
Section 3 The Respiratory System
Chapter 38
Respiratory Diseases
Respiratory diseases affect millions of Americans.
A chronic pulmonary—or lung—disease is one for which there is no cure.

53. Respiratory Diseases, continued
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Respiratory Diseases, continued
Asthma
Asthma is a chronic condition in which the bronchioles of the lungs become inflamed, resulting in a narrowing of the airways.
Prescribed inhalant medicines can help to stop an asthma attack by expanding the bronchioles.

54. Section 3 The Respiratory System
Chapter 38
Asthma

55. Respiratory Diseases, continued
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Respiratory Diseases, continued
Emphysema
Emphysema is a chronic pulmonary disease resulting from a chemical imbalance that destroys elastic fibers in the lungs. Emphysema damages or destroys the alveoli, causing constant fatigue and breathlessness.
Smoking causes up to 90 percent of emphysema cases.

56. Section 3 The Respiratory System
Chapter 38
Emphysema

57. Respiratory Diseases, continued
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Respiratory Diseases, continued
Lung Cancer
Lung cancer is a disease characterized by abnormal cell growth.
Smoking is the major cause of lung cancer.

58. Section 3 The Respiratory System
Chapter 38
Lung Cancer

59. Chapter 38 Multiple Choice
Standardized Test Prep
Multiple Choice
Use the chart below and your knowledge of science to answer questions 1–3.

60. Multiple Choice, continued
Chapter 38
Standardized Test Prep
Multiple Choice, continued
1. A person who consumes 23 g of salt per day is likely to have a systolic pressure of about
A. 120 mm Hg.
B. 130 mm Hg.
C. 140 mm Hg.
D. 150 mm Hg.

61. Multiple Choice, continued
Chapter 38
Standardized Test Prep
Multiple Choice, continued
1. A person who consumes 23 g of salt per day is likely to have a systolic pressure of about
A. 120 mm Hg.
B. 130 mm Hg.
C. 140 mm Hg.
D. 150 mm Hg.

62. Multiple Choice, continued
Chapter 38
Standardized Test Prep
Multiple Choice, continued
2. People with a normal systolic pressure likely have a daily salt intake that does not exceed
F. 4 g.
G. 16 g.
H. 19 g.
J. 27 g.

63. Multiple Choice, continued
Chapter 38
Standardized Test Prep
Multiple Choice, continued
2. People with a normal systolic pressure likely have a daily salt intake that does not exceed
F. 4 g.
G. 16 g.
H. 19 g.
J. 27 g.

64. Multiple Choice, continued
Chapter 38
Standardized Test Prep
Multiple Choice, continued
3. What conclusion can be drawn from the chart?
A. Increasing one’s salt intake leads to an increased systolic pressure.
B. Raising one’s systolic pressure leads to a greater appetite for salt.
C. A person can control hypertension by consuming more salt.
D. A daily salt intake of 10 g or less is associated with a risk to health.

65. Multiple Choice, continued
Chapter 38
Standardized Test Prep
Multiple Choice, continued
3. What conclusion can be drawn from the chart?
A. Increasing one’s salt intake leads to an increased systolic pressure.
B. Raising one’s systolic pressure leads to a greater appetite for salt.
C. A person can control hypertension by consuming more salt.
D. A daily salt intake of 10 g or less is associated with a risk to health.