1. Chapter 11 The Cardiovascular System
Essentials of Human Anatomy & Physiology
Seventh Edition
Elaine N. Marieb
Chapter 11 The Cardiovascular System
Slides 11.1 – 11.19
Lecture Slides in PowerPoint by Jerry L. Cook
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

2. Warm up:
Answer the following question in your notebooks or on a piece of paper.
1) What is the function of the cardiovascular (circulatory) system and what are it’s important parts?
REMINDER: your muscular system projects are due today.
You can turn them in tomorrow, but you will receive a 20% reduction in grade.

3. Next: Take notes on a piece of paper or in your notebooks.
I will come around and give you credit for them or you can turn them in.

4. The Cardiovascular System
A closed system of the heart and blood vessels
The heart pumps blood
Blood vessels allow blood to circulate to all parts of the body
The function of the cardiovascular system is to deliver oxygen and nutrients and to remove carbon dioxide and other waste products
Slide 11.1
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5. The Heart Location About the size of your fist
Thorax between the lungs
Pointed apex directed toward left hip
About the size of your fist
Slide 11.2a
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6. The Heart Figure 11.1 Slide 11.2b
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7. The Heart: Coverings Pericardium – a double serous membrane
Visceral pericardium
Next to heart
Parietal pericardium
Outside layer
Serous fluid fills the space between the layers of pericardium
Slide 11.3
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8. The Heart: Heart Wall Three layers Epicardium Myocardium Endocardium
Outside layer
This layer is the parietal pericardium
Connective tissue layer
Myocardium
Middle layer
Mostly cardiac muscle
Endocardium
Inner layer
Endothelium
Slide 11.4
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9. External Heart Anatomy
Figure 11.2a
Slide 11.5
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10. The Heart: Chambers Right and left side act as separate pumps
Four chambers
Atria
Receiving chambers
Right atrium
Left atrium
Ventricles
Discharging chambers
Right ventricle
Left ventricle
Slide 11.6
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11. Blood Circulation Figure 11.3 Slide 11.7
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12. Next:
You will have a heart to label and color.

13. Warm up: Answer the following question in your notebooks:
1) How do you think blood gets pumped into and around the heart?

14. The Heart: Valves Allow blood to flow in only one direction
Four valves
Atrioventricular valves – between atria and ventricles
Bicuspid valve (left)
Tricuspid valve (right)
Semilunar valves between ventricle and artery
Pulmonary semilunar valve
Aortic semilunar valve
Slide 11.8
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15. The Heart: Valves Valves open as blood is pumped through
Held in place by chordae tendineae (“heart strings”)
Close to prevent backflow
Slide 11.9
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16. Operation of Heart Valves
Figure 11.4
Slide 11.10
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17. The Heart: Associated Great Vessels
Aorta
Leaves left ventricle
Pulmonary arteries
Leave right ventricle
Vena cava
Enters right atrium
Pulmonary veins (four)
Enter left atrium
Slide 11.11
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18. Coronary Circulation
Blood in the heart chambers does not nourish the myocardium
The heart has its own nourishing circulatory system
Coronary arteries
Cardiac veins
Blood empties into the right atrium via the coronary sinus
Slide 11.12
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19. Next:
We are going write the steps to the movement of the valves in the heart together.

20. Warm up: Answer the following question in your notebook:
1) What do you think helps your heart beat the same each minute?

21. The Heart: Conduction System
Intrinsic conduction system (nodal system)
Heart muscle cells contract, without nerve impulses, in a regular, continuous way
Slide 11.13a
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22. The Heart: Conduction System
Special tissue sets the pace
Sinoatrial node
Pacemaker
Atrioventricular node
Atrioventricular bundle
Bundle branches
Purkinje fibers
Slide 11.13b
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23. Heart Contractions Contraction is initiated by the sinoatrial node
Sequential stimulation occurs at other autorhythmic cells
Slide 11.14a
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24. Heart Contractions Figure 11.5 Slide 11.14b
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25. Filling of Heart Chambers – the Cardiac Cycle
Figure 11.6
Slide 11.15
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26. The Heart: Cardiac Cycle
Atria contract simultaneously
Atria relax, then ventricles contract
Systole = contraction
Diastole = relaxation
Systole is the top number on your blood pressure and Diastole is the bottom number.
Slide 11.16
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27. Next:
You are going to
1) Draw arrows on the heart to indicate the direction of blood flow (blue and red)
2) Label the parts of the conduction system we just talked about.
3) Label the heart valves.

28. Filling of Heart Chambers – the Cardiac Cycle
Figure 11.6
Slide 11.15
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29. Heart Contractions Figure 11.5 Slide 11.14b
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30. Today: We are going to take notes over pulse.
Then, you will do a lab to measure each other’s pulse.
Please get a piece of paper out and a pencil so we can get started and get to the lab!

31. The Heart: Cardiac Cycle
Cardiac cycle – events of one complete heart beat
Mid-to-late diastole – blood flows into ventricles
Ventricular systole – blood pressure builds before ventricle contracts, pushing out blood
Early diastole – atria finish re-filling, ventricular pressure is low
Slide 11.17
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32. The Heart: Cardiac Output
Cardiac output (CO)
Amount of blood pumped by each side of the heart in one minute
CO = (heart rate [HR]) x (stroke volume [SV])
Stroke volume
Volume of blood pumped by each ventricle in one contraction
Slide 11.18
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33. Cardiac Output Regulation
Figure 11.7
Slide 11.19
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34. The Heart: Regulation of Heart Rate
Stroke volume usually remains relatively constant
Starling’s law of the heart – the more that the cardiac muscle is stretched, the stronger the contraction
Changing heart rate is the most common way to change cardiac output
Slide 11.20
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35. The Heart: Regulation of Heart Rate
Increased heart rate (Tachycardia)
Sympathetic nervous system
Crisis
Low blood pressure
Hormones
Epinephrine
Thyroxine
Exercise
Decreased blood volume
Slide 11.21
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36. The Heart: Regulation of Heart Rate
Decreased heart rate (Brachycardia)
Parasympathetic nervous system
High blood pressure or blood volume
Dereased venous return
Slide 11.22
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37. Taking Heart Rate Before and After Exercise:
Today we will do a lab to measure our heart rates before and after exercise.
You will first take your pulse while you are sitting still, then you will do some light exercise such as walking or side bends, then we will go out and you can do some vigorous exercise such as running or running up stairs.
You will take your pulse after each activity and we will then compare results with each other.
First, take your pulse while sitting, then we will go out the quad to do the exercise.

38. Blood Vessels: The Vascular System
Taking blood to the tissues and back
Arteries
Arterioles
Capillaries
Venules
Veins
Slide 11.23
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39. Differences Between Blood Vessel Types
Walls of arteries are the thickest
Lumens (interior) of veins are larger
Skeletal muscle “milks” blood in veins toward the heart.
Walls of capillaries are only one cell layer thick to allow for exchanges between blood and tissue
Slide 11.26
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40. The Vascular System Figure 11.8b Slide 11.24
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41. Blood Vessels: Anatomy
Three layers (tunics)
Tunic intima
Endothelium
Tunic media
Smooth muscle
Controlled by sympathetic nervous system
Tunic externa
Mostly fibrous connective tissue
Slide 11.25
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42. Movement of Blood Through Vessels
Most arterial blood is pumped by the heart
Veins use the milking action of muscles to help move blood
Figure 11.9
Slide 11.27
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43. Capillary Beds Capillary beds consist of two types of vessels
Vascular shunt – directly connects an arteriole to a venule
Figure 11.10
Slide 11.28a
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44. Capillary Beds True capillaries – exchange vessels
Oxygen and nutrients cross to cells
Carbon dioxide and metabolic waste products cross into blood
Figure 11.10
Slide 11.28b
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45. Diffusion at Capillary Beds
Figure 11.20
Slide 11.29
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46. Major Arteries of Systemic Circulation
Figure 11.11
Slide 11.30
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47. Major Veins of Systemic Circulation
Figure 11.12
Slide 11.31
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48. Major Arteries of the Systemic Circulation
Aorta: is the largest artery of the body.
In adults, it is the size of a garden hose. (internal diameter the size of a thumb)
The ascending aorta springs from the left ventricle of the heart.
It arches left as the aortic arch.
It plunges downward through the thorax following the spine as the thoracic aorta.
It then passes through the diaphragm into the abdominopelvic cavity, where it becomes the abdominal aorta.

49. Arterial Branches of Ascending Aorta and Aortic Arch:
The only branches of the ascending aorta are the right (R.) and left (L.) coronary arteries, which serve the heart.
The brachiocephalic trunk (first branch off the aortic arch) splits into the R. common carotid artery and R. subclavian artery.
The L. common carotid artery is the second branch off the aortic arch.
It divides forming the L. internal carotid, which serves the brain, and the L. external carotid, which serves the skin and muscles of the head and neck.

50. Today: We are going to take more notes over different blood vessels.
Then, you will have some coloring labeling to do of the different veins and arteries.

51. Arterial Branches of the Aortic Arch:
The third branch of the aortic arch, the L. subclavian artery, gives off an important branch – the vertebral artery, which serves the brain.
In the axilla, the subclavian artery becomes the axillary artery and then continues into the arm as the brachial artery, which splits to form the radial and ulnar arteries, which serve the forearm.

52. Arterial Branches of the Thoracic Aorta:
The intercostal arteries (ten pairs) supply the muscles of the thorax wall.
Other branches of the thoracic aorta supply the lungs (bronchial arteries) the esophagus ( esophageal arteries), and the diaphragm ( phrenic arteries).

53. Arterial Branches of the Abdominal Aorta:
The celiac trunk is the first branch of the abdominal aorta.
It is a single vessel that has three branches
1) The L. gastric artery supplies the stomach.
2) The splenic artery supplies the spleen.
3) The common hepatic artery supplies the liver.

54. The Arterial Branches of the Abdominal Aorta:
The unpaired superior mesenteric artery supplies most of the small intestine and the first half of the large intestine, or colon.
The renal (R. and L.) arteries serve the kidneys.
The gonadal (R. and L.) supply the gonads.
They are called the ovarian arteries in females and the testicular arteries in males.

55. The Arterial Branches of the Abdominal Aorta:
The inferior mesenteric artery is a small, unpaired artery supplying the second half of the large intestine.
The common iliac (R. and L.) arteries are the final branches of the abdominal aorta.
Each divides into an internal iliac artery, which supplies the pelvic organs , and the external iliac artery, which enters the thigh, where it becomes the femoral artery.
The femoral artery and its branch the deep femoral artery, serve the thigh.

56. The Arterial Branches of the Abdominal Aorta:
At the knee, it becomes the popliteal artery, which then splits into the anterior and posterior tibial arteries which supply the leg and foot.
The anterior tibial artery terminates in the dorsalis pedis artery, which supplies the dorsum of the foot.

57. Next:
You are going to color and label the veins and arteries of the circulatory system.
Pay close attention because these will be important for our dissection!

59. Today: We are going to talk about the major veins.
Then, you will identify each of the veins and arteries by their functions.

60. Major Veins of Systemic Circulation:
Arteries are usually deeper, and veins are usually superficial.
Most deep veins follow the course of major arteries.
Major arteries branch off the aorta, while the veins converge on the venae cavae.
Veins draining the head and arms empty into the superior vena cava, and those draining the lower body empty into the inferior vena cava.

61. Veins Draining into the Superior vena cava:
The radial and ulnar veins – drain the forearm
Unite to form the brachial vein – drains the arm and empties into the axillary vein in the axillary region.
The cephalic vein – provides drainage of the lateral aspect of the arm and empties into the axillary vein.
The basilic vein is a superficial vein that drains the medial aspect of the arm and empties into the brachial vein.

62. Veins Draining into the Superior vena cava:
The basilica and cephalic veins are joined at the anterior aspect of the elbow by the median cubital vein.
The subclavian vein receives venous blood from the arm through the axillary vein and from the skin and muscles of the head through the external jugular vein.
The vertebral vein drains the posterior part of the head.

63. Veins Draining into the Superior vena cava:
The internal jugular vein drains the dural sinuses of the brain.
The brachiocephalic veins are large veins that receive venous drainage from the subclavian, vertebral, and internal jugular veins on their respective sides.
They join to form the superior vena cava which enters the heart.

64. Veins that drain into the inferior vena cava:
The anterior and posterior tibial veins and the fibular vein drain the leg.
The posterior tibial vein becomes the popliteal vein at the knee and then the femoral vein in the thigh.
The femoral vein becomes the external iliac vein as it enters the pelvis.

65. Veins Draining into the Superior vena cava:
The great saphenous veins are the longest veins of the body. They receive superficial drainage of the leg.
They begin at the dorsal venous arch in the foot and travel up the medial aspect of the leg to empty into the femoral vein in the thigh.
Each common iliac vein is formed by the union of the external iliac vein and the internal iliac vein (drains the pelvis).
These combine to form the inferior vena cava.

66. Veins Draining into the Superior vena cava:
The renal veins drain the kidneys.
The hepatic portal vein is a single vein that drains the digestive tract organs and carries this blood through the liver before it enters the systemic circulation.
The hepatic veins drain the liver.

67. Next:
You will identify each of the veins and arteries based on their function.
Their function will help you locate them especially when we do the pigs.

69. Arterial Supply of the Brain
Figure 11.13
Slide 11.32
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70. Arterial Supply to the Brain and Circle of Willis:
1.The internal carotid arteries are branches of the common carotid arteries, run through the neck and enter the skull through the temporal bone.
2. Once inside the cranium, each divides into anterior and middle cerebral arteries, which supply most of the cerebrum.
3. The paired vertebral arteries pass upward from the subclavian arteries at the base of the neck.

71. Arterial Supply to the Brain and Circle of Willis:
4. Within the skull, the vertebral arteries join to form a single basilar artery, which serves the brain stem and cerebellum as it travels upward.
5. At the base of the cerebrum, the basilar artery divides to form the posterior cerebral arteries, which supply the posterior part of the cerebrum.
The anterior and posterior blood supplies of the brain are united by small communicating arterial branches.

72. Arterial Supply to the Brain and Circle of Willis:
6. The result is a complete circle of connecting blood vessels called the circle of Willis, which surrounds the brain.
The circle of Willis protects the brain by providing more than one route for blood to reach brain tissue in case of a clot or impaired blood flow anywhere in the system.

73. Hepatic Portal Circulation
Figure 11.14
Slide 11.33
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74. Hepatic Portal Circulation:
1. The veins of hepatic portal circulation drain the digestive organs, spleen, and pancreas and deliver this blood to the liver through the hepatic portal vein.
When you have just eaten, the hepatic portal vein contains large amounts of nutrients.
Since the liver is a key body organ involved in maintaining proper glucose, fat, and protein concentrations in blood, this system “tales a detour” to ensure that the liver processes these substances before they enter the systemic circulation.

75. Hepatic Portal Circulation:
2. The inferior mesenteric vein, draining the terminal part of the large intestine, drains the splenic vein, which itself drains the spleen, pancreas, and left side of the stomach.
The splenic vein and superior mesenteric vein join to form the hepatic portal vein.
3. The L. gastric vein, which drains the right side of the stomach, drains into the hepatic portal vein.

76. Circulation to the Fetus
Figure 11.15
Slide 11.34
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77. Fetal Circulation
Since the lungs and digestive system are not yet functioning in a fetus, all nutrient, excretory, and gas exchanges occur through the placenta.
Nutrients and oxygen move from the mother’s blood into the fetal blood, and fetal wastes move in the opposite direction.

78. Fetal Circulation:
1. The umbilical cord contains three blood vessels: one large umbilical vein and two smaller umbilical arteries.
The umbilical vein carries blood rich in nutrients and oxygen to the fetus.
The umbilical arteries carry carbon dioxide and debris-laden blood from the fetus to placenta.

79. Fetal Circulation:
2. As blood flows superiorly toward the heart of the fetus, most of it bypasses the immature liver through the ductus venosus and enters the inferior vena cava, which carries the blood to the right atrium of the heart.
3. Some of the blood entering the right atrium is shunted directly into the left atrium through the foramen ovale.

80. Fetal Circulation:
The ductus arteriosus is a short vessel that connects the aorta and the pulmonary trunk.
4. At birth, or shortly after, the foramen ovale closes, and the ductus arteriosus collapses and is converted to the fibrous ligamentum arteriosum.
As blood stops flowing through the umbilical vessels, they become obliterated, and the circulatory pattern converts to that of an adult.

81. Today: We will review for our artery and vein quiz.
The quiz will be Friday and we will have to wait to do our pigs until next Wednesday.

82. Major arteries of the body:
Carotid
Vertebral
Subclavian
Brachial
Radial
Ulnar
Axillary
Renal
Common Iliac
Femoral
Popliteal
Dorasalis Pedis
Coronary

83. Major Veins of the Body:
External Jugular
Subclavian
Superior Vena Cava
Brachial
Axillary
Median Cubital
Inferior Vena Cava
Hepatic Portal Vein
Common Iliac
Renal
Femoral
Greater Saphenous
Popliteal
Dorsal Venous Arch

84. Today:
We are going to talk about pulse and blood pressure.

85. Pulse 1. Pulse – pressure wave of blood
2. Monitored at “pressure points” where pulse is easily palpated
Figure 11.16
Slide 11.35
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86. Blood Pressure Gradient:
1. When the ventricles contract, they force blood into large, thick-walled elastic arteries that expand as the blood is pushed into them.
2. The high pressure in these arteries forces the blood to continually move into areas where the pressure is lower.
3. The pressure is highest in the large arteries and continues to drop throughout the pathway, reaching zero or negative pressure at the venae cavae.

87. Blood Pressure Gradient:
4. As blood flows it flows through the smaller arteries, then arterioles, capillaries, venules, veins, and finally back to the large venae cavae entering the right atrium of the heart.
5. It flows continually along the pressure gradient (from high to low pressure) as it makes its circuit day in and day out.
6. If venous return depended entirely on high blood pressure in the system, then blood would probably never be able to complete its circuit back to the heart.

88. Blood Pressure Gradient:
7. The pressure differences between veins and arteries becomes very clear when they are cut.
8. When a vein is cut, the blood flows evenly from the wound; but a lacerated artery produces rapid spurts of blood.
9. Continual blood flow depends on the stretchiness of the larger arteries and their ability to recoil and keep the pressure on the blood as it flows off into the circulation.

89. Blood Pressure Gradient:
10. The importance of elasticity of the arteries is best appreciated when it is lost, as in arteriosclerosis.
11. Arteriosclerosis is hardening of the arteries.

90. Blood Pressure
Measurements by health professionals are made on the pressure in large arteries and are known as sounds of Kortokoff.
1. Systolic – pressure at the peak of ventricular contraction
2. Diastolic – pressure when ventricles relax
3. Pressure in blood vessels decreases as the distance away from the heart increases
Slide 11.36
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91. Measuring Arterial Blood Pressure
Figure 11.18
Slide 11.37
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92. Comparison of Blood Pressures in Different Vessels
Figure 11.17
Slide 11.38
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93. Blood Pressure: Effects of Factors
1. Neural factors
Autonomic nervous system adjustments (sympathetic division)
A. Causing vasoconstriction – narrowing of the blood vessels, which increases blood pressure
Example: When we stand up suddenly after lying down, the effect of gravity causes blood to pool in the vessels of the legs and feet, and blood pressure drops.
Slide 11.39a
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94. Example (Continued)
This activates presorreceptors in the large arteries of the neck and chest.
They send off warning signals that result in reflexive vasoconstriction, which increases blood pressure back to homeostatic levels.
Another example is when we exercise vigorously or are frightened and have to make an escape.
Under these conditions, there is a generalized vasoconstriction except in the skeletal muscles.
Blood vessels in the skeletal muscles dilate to increase the blood flow to the working muscles.

95. Blood Pressure: Effects of Factors
2. Renal factors
A. Regulation by altering blood volume
B. Renin – hormonal control
As blood pressure and/ or volume increases beyond normal, the kidneys allow more water to leave the body in urine. Since the source of the water is the blood stream, blood volume decreases, which in turn decreases blood pressure.
This also can work the opposite way.

96. Blood Pressure: Effects of Factors
3. Temperature
A. Heat has a vasodilation effect
B. Cold has a vasoconstricting effect (why your skin feels cold).
4. Chemicals
A. Various substances such as drugs and hormones can cause increases or decreases.
B. Epinephrine increases both heart rate and blood pressure.
C. Nicotine increases blood pressure by causing vasoconstriction.
D. Alcohol causes vasodilation and decreases blood pressure. (causing you to become flushed)
Slide 11.39b
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97. Blood Pressure: Effects of Factors
5. Diet:
A. It is generally believed that a diet low in salt, saturated fats, and cholesterol helps to prevent hypertension, or high blood pressure.

98. Factors Determining Blood Pressure
Figure 11.19
Slide 11.40
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99. Next:
There are many causes of high blood pressure, especially in society today.
Look up 3 different causes of high blood pressure and write two paragraphs about how high blood pressure is caused and how it can be prevented.
Your quiz over the cardiovascular system will be next Tuesday.
I will hand out study guides for you tomorrow.

100. Variations in Blood Pressure
Human normal range is variable
Normal
140–110 mm Hg systolic
80–75 mm Hg diastolic
Hypotension
Low systolic (below 110 mm HG)
Often associated with illness
Hypertension
High systolic (above 140 mm HG)
Can be dangerous if it is chronic
Slide 11.41
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101. Capillary Exchange Substances exchanged due to concentration gradients
Oxygen and nutrients leave the blood
Carbon dioxide and other wastes leave the cells
Slide 11.42
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102. Capillary Exchange: Mechanisms
Direct diffusion across plasma membranes
Endocytosis or exocytosis
Some capillaries have gaps (intercellular clefts)
Plasma membrane not joined by tight junctions
Fenestrations of some capillaries
Fenestrations = pores
Slide 11.43
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103. Developmental Aspects of the Cardiovascular System
A simple “tube heart” develops in the embryo and pumps by the fourth week
The heart becomes a four-chambered organ by the end of seven weeks
Few structural changes occur after the seventh week
Slide 11.44
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104. Next: Today: I have your chapter 11 Study guides for you.
Your chapter 11 test will be next Wednesday.
Please work on them and complete at least the first page today.
Get them stamped before you leave.

105. 1. Blood enters the right atrium from the superior and inferior venae cavae,
and the coronary sinus.
2. From right atrium, it goes through the tricuspid valve to the right ventricle.
3. From the right ventricle, it goes through the pulmonary semilunar valves to
the pulmonary trunk.
4. From the pulmonary trunk it moves into the right and left pulmonary arteries to the lungs.
5. From the lungs, oxygenated blood is returned to the heart through the pulmonary veins.
6. From the pulmonary veins blood flows into the left atrium.
7. From the left atrium, blood flows through the bicuspid (mitral) valve into the left ventricle.
8. From the left ventricle, it goes through the aortic semilunar valves into the ascending aorta.
9. Blood is distributed to the rest of the body (systemic circulation) from the aorta.

108. Homeostatic Imbalance:
Congenital heart defects account for about half of infant deaths resulting from all congenital defects.
Environmental interferences, such as maternal infection and ingested drugs during the first three months of pregnancy (when the heart is forming), seem to be major causes of most problems.
Congenital heart defects may include a ductus arteriosus that does not close, septal openings, and other structural abnormalities of the heart.
Such problems can usually be corrected surgically.

109. Developmental Aspects of the Cardiovascular System:
Without congenital heart problems, the heart usually functions smoothly throughout life.
Homeostatic mechanisms are so efficient, that we rarely even realize when the heart is working harder.
The heart will hypertrophy (grow) and its cardiac output will increase if we exercise regularly and aerobically.
The heart becomes a more efficient pump and pulse rate and blood pressure decrease.

110. Developmental Aspects of the Cardiovascular System:
Another benefit of aerobic exercise is that it clears fatty deposits from blood vessel walls, helping to slow the progress of arteriosclerosis.
However, if you do not exercise regularly, you may push your heart too much which could lead to a myocardial infarction, or a heart attack.

111. Developmental Aspects of the Cardiovascular System:
As we get older, more symptoms of cardiovascular disturbances start to appear.
In some, the venous valves weaken, and purple snakelike varicose veins appear.
Not everyone has varicose veins, but we all have progressive atherosclerosis.
This leads to hypertension (high blood pressure) and hypertensive heart disease (high pulse).

112. Developmental Aspects of the Cardiovascular System:
The filling of the blood vessels with fatty, calcified deposits leads to coronary artery disease.
At least 30% of the population in the U.S. has hypertension by age 50, and cardiovascular disease causes over ½ of deaths over age 65.
Researchers believe that diet, not aging is the single most important contributing factor to cardiovascular disease.
It is believed that the risk is lowered if people eat less animal fat, cholesterol, and salt.
Regular exercise, avoiding stress, and not smoking are other recommendations for heart health.

113. Today:
I will give you about 10 minutes to finish your study guides, then we will go over them.
If you are note finished, you will need to step outside while we go over them.

114. Next:
Do multiples choice questions #1-10 on pages and turn them in when you are done.

115. Today: You have your chapter 13 test.
Please place your backpacks up front and your phones on my desk.
When you’re finished, turn in your test and you make work on other work for other classes or you may sit quietly.