1. THE HEART http://www.youtube.com/watch?v=0Vn5AJ_Mjfs&NR=1

2. UNIT K: HEART STRUCTURE & FUNCTION (Ch. 13, pp. 228-233)
K1. Identify & give functions for the following:
Left and right atria
Left and right ventricles
Coronary arteries and veins
Anterior and posterior vena cava
Aorta
Pulmonary arteries and veins
Pulmonary trunk
Atrioventricular valves
Chordae tendinaea
Semi-lunar valves
Septum

3. K2. Describe the location and functions of the SA node, AV node, and Purkinje fibers
K3. Describe the autonomic regulation of the heartbeat by the nervous system
K4. Relate factors that affect and regulate blood pressure to hypertension and hypotension
K5. Demonstrate the measurement of blood pressure
K6. Distinguish between systolic and diastolic pressure

4. VOCABULARY _____ Aorta _____ Inferior Vena Cava _____ Aortic valve
_____ Atrioventricular (AV) valves
_____ Atrium
_____ Autonomic nervous system
_____ AV node
_____ Blood pressure
_____ Brachial artery
_____ Bundle of His
_____ Chordae tendineae
_____ Constrict
_____ Coronary arteries
_____ Coronary veins
_____ Dilate
_____ Hypertension
_____ Hypotension
_____ Hypothalamus
_____ Inferior Vena Cava
_____ Medulla oblongata
_____ Pacemaker
_____ Pulmonary artery
_____ Pulmonary circuit
_____ Pulmonary trunk
_____ Pulmonary valve
_____ Pulmonary vein
_____ Purkinje fibres
_____ SA node
_____ Semi-lunar valve
_____ Septum
_____ Superior Vena Cava
_____ Systemic circuit
_____ Vagus nerve
_____ Ventricle

5. Amazing Heart Facts Put your hand on your heart. Where is it?
Hold out your hand and make a fist.
size of heart: child = 1 fist; adult = 2 fists!
Your heart beats about 100,000 times in one day and about 35 million times in a year.
During an average lifetime, the human heart will beat more than 2.5 billion times.
Sure, you know how to steal hearts, win hearts, and break hearts. But how much do you really know about your heart and how it works?
Even at rest, the muscles of the heart work twice as hard as the leg muscles of a person sprinting

6. approximately 10 seconds
In one day, the blood travels a total of 19,000 km. That's 4 times the distance across CANADA from coast to coast.
When you are resting, it takes seconds for the blood to move through your body. What about when you are exercising?
approximately 10 seconds
How much does your heart weigh?
only 2/3 of a pound!
Give a tennis ball a good, hard squeeze. You're using about the same amount of force your heart uses to pump blood out to the body

7. Basic Functions of the Circulatory System
Transports oxygen from the lungs to body to be used 1
Transports carbon dioxide and hydrogen ions to the lungs to be removed 2
Transports nutrients from the small intestine to tissues 3
Fights infections 4

8. Transports water from the digestive system to the body and lungs5
Carries waste products (ie: urea) to kidneys for removal in urine 6
Distributes body heat from internal source to skin (to get rid of it) 7
Seals wounds by forming blood clots 8

9. Transports hormones around the body9
Maintains pH in tissues (acts as a buffer with HHb) 10
Regulates fluid levels in tissues (with Lymphatic system) 11

10. ANATOMY OF THE HEART

11. Where is it?

15. The Parts
You Need
To Know!

16. The human heart has 4 well developed chambers
Right Atrium
Left Atrium
Right Ventricle
The right side of the heart feeds the pulmonary circuit, and the left side feeds the systemic circuit.
Left Ventricle

17. The right side of the heart pumps deO2 blood to the lungs.
PULMONARY
The left side of the heart pumps O2 blood to the body
SYSTEMIC

18. the receiving chambers
ATRIA
the receiving chambers
Left Atrium
Right Atrium
Receives oxygenated blood from the lungs via the pulmonary veins
Receives deoxygenated blood from the body via the anterior & posterior vena cava.

19. ATRIOVENTRICULAR VALVES
Tricuspid Valve
1. Separate the atria from the ventricles.
Bicuspid Valve
2. They open when the atria contract.
these flaps of tissue separate the atria from the ventricles. When blood pressure is greater in the atria (and the atria contract), the valves open and blood enters the ventricles on each side.
3. They prevent the blood from going backwards when the ventricles contract.

20. bicuspid
valve
tricuspid
valve

21. the real thing

22. Bicuspid Valve

23. CHORDAE TENDINAE Tendon-like pieces of tissue
They keep the AV valves from inverting when the ventricles contract
Point out that this is a TRI-CUSPID valve because it has 3 cusps.

24. They hold & support the chordae tendinae
PAPILLARY MUSCLE

25. Can’t open properly
Closed
Open
Can’t close properly
     
     
     
     
     
Normal Heart Valves
Heart Murmur

26. VENTRICLES the sending chambers Right Ventricle
When the right atrium contracts, it pushes the blood through the tricuspid valve and into the right ventricle.
When the RIGHT VENTRICLE contracts, BP forces the TRICUSPID valve to close.
The BP forces PULMONARY VALVE open & the blood moves into the PULMONARY TRUNK.
Right Ventricle

27. AT THE LUNGS The PULMONARY ARTERIES take the deO2 blood to the lungs.
The CO2 is removed from the blood and is replaced with O2.
AT THE LUNGS
The PULMONARY VEINS take the O2 blood to the heart.

29. What carries the Oxygen?
The protein HEMOGLOBIN binds the O2 tightly and carries it to the body cells as OXYHEMOGLOBIN!

30. pulmonary
systemic

31. SEPTUM separates the 2 sides
A muscular wall that separates the right side of the heart from the left side.
Keeps the deO2 blood from mixing with the O2 blood

32. hole in the septum
Some people are born with a hole in their septum

34. When the left atrium contracts, it pushes the blood through the bicuspid valve and into the left ventricle.
When the LEFT VENTRICLE contracts, the BICUSPID VALVE is forced closed.
Blood is forced through the AORTIC VALVE and enters the AORTA.
Left Ventricle
The left ventricle has a THICKER muscle layer. WHY?

35. AORTA the biggest artery Aortic Arch Dorsal Aorta To the head
To the arms & lungs
Aortic Arch
Coronary Artery: to the heart
Dorsal Aorta
To the lower body
the biggest artery
The aorta takes O2 blood to the body.

36. CORONARY ARTERIES & VEINS
The first branches of the aorta take the blood to the coronary arteries.
Takes blood into the heart muscle itself. The coronary veins return the deO2 blood to the vena cava  right atrium.

37. VENA CAVA Superior Vena Cava Inferior Vena Cava
These are the BIGGEST VEINS!
They bring the deO2 blood back to the heart so that it can be pumped to the lungs.
Inferior Vena Cava

38. exterior view of the heart
Aortic Arch
Superior vena cava
Pulmonary Trunk
Coronary artery
Right Atrium
Coronary Vein
Right Ventricle
Left Ventricle
Inferior Vena Cava

40. draw the arrows Aortic Arch Superior Vena Cava Left Pulmonary Artery
                                                                                                                                                                                                         
Aortic Arch
Superior Vena Cava
Left Pulmonary Artery
Right Pulmonary Artery
Pulmonary Trunk
Left Pulmonary Veins
Right Pulmonary Veins
Left Atrium
Bicuspid (AV) Valve
Right Atrium
Pulmonary (semi-lunar) Valve
Aortic (semi-lunar) Valve
Left Ventricle
Tricuspid (AV) Valve
Right Ventricle
Inferior Vena Cava
Dorsal Aorta

43. this all happens at once!
Keep in mind that
this all happens at once!

44. CONTROL OF
HEART FUNCTION

45. Why can
a heart keep beating
outside of the body? ?

46. Coordination of the Beating
• Heart cells naturally beat slowly if ATP is present
• If there was no coordination, the heart cells would all beat randomly
Beating Human Heart:

47. How Does The Heart Work to Pump The Blood
There are two spots of specialized tissue in the heart.
Both are located in the right atrium.
Nodal tissue is unique: made of specialized muscle cells combined with nerve cells.
It has the ability to contract independent of other stimuli.

48. The SA NODE (sino-atrial)
This node is found along the wall of the right atrium chamber.
It fires on average, every 0.85 seconds (or 72 times per minute).
It stimulates the simultaneous contraction of the atria.
It also sends a nerve impulse along a nerve trunk called the BUNDLE OF HIS to the AV NODE

49. S A
NODE

50. The SA node initiates the heartbeat and has been given the nickname of the “PACEMAKER”
a small electronic device that stimulates the SA node to fire
You can ‘re-set’ your pacemaker by calling a number and holding the phone up to your heart. COOL!
People with irregular heartbeats may have to have an artificial pacemaker ‘inserted’.

51. PACEMAKER

52. The AV NODE (atrioventricular)
In the right atrium close to the AV (tricuspid) valve
When the AV node receives the impulse from the SA node, it fires to initiate the contraction of the LARGE ventricles
A.V. NODE
PURKINJE FIBRES
Because the ventricles are so massive (as compared to the atria), the AV node works through the PURKINJE FIBRES, a set of nerves that conducts impulses throughout the ventricles. The P. F. contract in unison & cause the ventricles to contract at the same time from the bottom, upwards.
The AV node sends its message through the P.F., which cause ventricles to contract.

53. A V
NODE
&
Purkinje fibres

54. the pacemaker cells WHY?
• Atria beat from top down, then pause, and the ventricles beat from bottom up.
WHY?

55. E K G http://www.youtube.com/watch?v=ew6Jp74vaN4
See page

56. FROG DISECTION http://www.youtube.com/watch?v=fO7lBX5CSxw

57. There are two parts to the contraction of the heart
EKG
The heart beat is a double sound (‘lub-dub’).
An EKG (electrocardiogram) registers the voltage changes across the surface of the heart as it beats.
The letters PQRST are the standard labels used to identify the parts of the EKG.

58. P = the simultaneous contraction of the atria (caused by SA node)
QRS = the contraction of the ventricles (caused by AV node & purkinje fibres)
P: as atria contract blood is forced into ventricles
QRS: as ventricles contract, blood is forced into arteries
T: restoration of normal electrical condition; preparation for subsequent contraction.
T = the recovery of the ventricles (preparation for next contraction)

59. KNOW THIS DIAGRAM! R Q P S T
KNOW THIS DIAGRAM!!

61. Some Abnormal EKG’s NORMAL
Tachycardia (a heart rate of over 100 beats/min)
Ventricular Fibrillation (uncoordinated ventricles)
Heart Block (failure to stimulate ventricles after atrial contraction)

62. This is known as defibrillation
If the system really breaks down, the heart could go into fibrillation. This is uncoordinated contractions of the cardiac muscle.
When this happens, the pacemaker (SA NODE) will send a strong shock through the heart.
Hopefully the heart muscle will reset itself.
This is known as defibrillation

63. defibrillator
We also try to do this artificially when people are in cardiac arrest!

65. HOW IS THE BRAIN
INVOLVED

66. The natural average resting heart rate is 72 beats per minute
The SA node is connected to the brain by the VAGUS NERVE (cranial nerve #10).

68. The regulation of the heartbeat is under the influence of the AUTONOMIC NERVOUS SYSTEM (not under conscious control)
Sympathetic Nervous System: When the brain is not receiving blood quickly enough, the brain will signal the SA node (via the vagus nerve) to speed up its contraction. This will usually occur in circumstances of FIGHT or FLIGHT. It will also occur when the blood pressure is too low.
Parasympathetic Nervous System: this system will reestablish the resting heart rate (~60-70 beats/minute) by sending a message via the vagus nerve to slow the heart rate.
Sympathetic (fight or flight): causes heart to speed up
Parasympathetic: causes heart to slow down (via vagus nerve)

69. The part of the brain that governs the speed of the heart rate is called the MEDULLA OBLONGATA
It will speed up or slow down the heart rate when needed. **Under normal circumstances, the heart controls itself.

70. Problems Of The Heart

71. Hardening of the arteries
atherosclerosis

73. Cholesterol in the blood can become deposited on the inside walls of the arteries. This seems to happen faster in people who:   •Smoke
•Have high blood pressure
•Eat high fat, high cholesterol foods, or, for other reasons, have high cholesterol
•Are overweight
•Have a lot of tension and stress
•Do not exercise regularly
•Have diabetes and/or family members with a history of atherosclerosis

75. burst coronary artery

76. in men

77. in women

79. heart attack !

82. Before it gets to this point....

83. Heart Bypass Surgery

84. After surgery

85. If it gets too bad to repair...
Heart Transplant

86. Perform your own heart transplant: http://www. pbs

87. If there isn't one available...
Abiocor Heart
Made from titanium metal and a special type of plastic.
A rechargeable internal battery
Normally an external power pack transmits power across the skin.

88. BLOOD PRESSURE

89. What is YOUR pulse rate at rest? After exercise?
Feel your pulse by placing two fingers at pulse points on your neck or wrists. Now count the beats for 15 seconds & multiply by 4.
As a kid, your resting pulse might range from 90 to 120 beats per minute.
As an adult, your pulse rate slows to an average of 72 beats per minute.
1. The pulse you feel is blood stopping and starting as it moves through your arteries. As a kid, your resting pulse might range from 90 to 120 beats per minute. As an adult, your pulse rate slows to an average of 72 beats per minute.
What is YOUR pulse rate at rest? After exercise?

90. BLOOD PRESSURE: the ventricles pump approx
BLOOD PRESSURE: the ventricles pump approx. 70 mL of blood each time they contract.
The pulse you feel is blood stopping and starting as it moves through your arteries.

91. Blood is being forced through the arteries (approx. 120 mmHg)
Blood pressure is not constant, it fluctuates with each heartbeat.  
SYSTOLIC PRESSURE (systole): blood pressure when the ventricles are contracting.
Blood is being forced through the arteries (approx. 120 mmHg)

92. DIASTOLIC PRESSURE (diastole): blood pressure as ventricles are refilling.
This is between contractions, and the blood pressure is less (appox 80 mmHg).

94. A reading of 120/80 mmHg is normal.
Blood pressure is normally measured along the BRACHIAL ARTERY of the arm.
A reading of 120/80 mmHg is normal.

95. When you are younger, your BP will be higher.
Example: yrs. will be
over 86-92

96. HIGH BLOOD PRESSURE (ie: 150/100)
HYPERTENSION
HIGH BLOOD PRESSURE (ie: 150/100)

97. Limit Alcohol Be Active Eat less salt Don’t Smoke Lose Weight
High blood pressure sometimes goes unnoticed until complications set in.
Limit Alcohol
Be Active
Eat less salt
Don’t Smoke
Lose Weight
Eat Healthy

98. High Blood Pressure puts constant strain on the tissues (especially the capillary beds).
May cause capillaries to burst
If this happens in the brain = a stroke If it happens in the heart = heart attack!
The longer you have high BP, the greater the potential for tissue damage.
Sometimes high BP is normal (ie: when doing physical activity)
However, the brain should return the BP to a normal, lower level.

99. LOW BLOOD PRESSURE (ie: 100/60)
HYPOTENSION
LOW BLOOD PRESSURE (ie: 100/60)

100. Low blood pressure is not particularly a good thing either.
It can result from:
Genetics
Anemia *not enough iron*
Dehydration *not enough water*
Blood loss
Shock
Proper kidney function can only be maintained if there is sufficient pressure for filtration.

101. What Factors Affect
Blood Pressure?

102. bigger (dilate) = lower BP smaller (constrict) = higher BP
Vessel diameter:
bigger (dilate) = lower BP smaller (constrict) = higher BP
Vasodilation to lower BP
Our bodies can adjust blood pressure. The Hypothalamus monitors our blood pressure and controls the size of our arterioles. The body can dilate (widen) arterioles to lower blood pressure [vasodilation] OR constrict (narrow) arterioles to raise the blood pressure [vasoconstriction].
Vasoconstriction to increase BP

103. Blood viscosity:
Thick blood (little water) = higher BP Thin (lots of water) = lower BP
More water in our blood means decreased viscosity and lower resistance and blood pressure.

104. More fat = more vessels = more resistance = increased BP
Total blood vessel length:
More fat = higher BP Thinner = lower BP
More fat = more vessels = more resistance = increased BP

105. ATHEROSCLEROSIS (hardening of arteries = decreased elasticity).
Vessel elasticity: affected by plaques (fatty deposits).
Elastic vessels = lower BP Hardened vessels = high BP
Atherosclerosis - accumulation of soft masses of fatty material, esp. cholesterol, beneath inner linings of arteries. These protrude and interfere with blood flow and increase blood pressure. The presence of hard plaque on artery walls can cause blood to form clots. If the clots stay in place they will block blood flow in the artery (thrombus). An embolus occurs if the clot moves. An embolus causes an embolism when it stops and blocks off a smaller blood vessel. This causes a heart attack if the artery is a coronary artery or a stroke if it is an artery in the brain.
ATHEROSCLEROSIS (hardening of arteries = decreased elasticity).

106. Blood volume:
Eat lots of salt = more volume/water stays in body = higher BP
Sweat a lot = less volume/water = lower BP
Diet and lifestyle are often to blame for elevated blood pressure. High salt intake from diet or kidneys will increase BP. Excessive salt will retain water in the body – greater fluid volume leads to greater blood pressure.

107. Cardiac output:
Heart rate increases = higher BP Heart rate decreases = lower BP
Stress can also cause high blood pressure. The brain controls all of these increases and decreases in blood pressure. One way that it can control BP (other than vaso-contriction/dilation of arterioles) if to increase and decrease the heart rate. This is controlled by the vagus/parasympathetic nerve (which decreases heart rate), and the sympathetic nerve (which during stress increases the heart rate).

108. Young = very elastic = low BP
Age: as you get older, there is a loss of elasticity in the blood vessels.
Young = very elastic = low BP
Old = not elastic = high BP

109. Stressed = constricted vessels = Higher BP
Stress: constricts blood vessels which means increased pressure to move the blood.
Stressed = constricted vessels = Higher BP
Calm = normal vessels = Lower BP

110. Heart Animations and Interactives
Animation: Your heart valves at work
Interactive: Label the heart
Interactive: Listen to the heart with a virtual stethoscope
Interactive: Explore the structures of the heart and trace the pathway of blood through the heart, lungs, and body
Animation: See the flow of blood to and from the exterior heart