UNIT K
THE HEART AND BLOOD PRESSURE
(Ch. 13, pp. 228-233)
WHAT DO I NEED TO KNOW?
K1. Identify & give functions for the following:
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Left and right atria
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Pulmonary arteries and veins
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Left and right ventricles
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Pulmonary trunk
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Coronary arteries and veins
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Atrioventricular valves
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Anterior and posterior vena
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Chordae tendinaea
cava
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Semi-lunar valves
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Aorta
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Septum
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
VOCABULARY
_____ Aorta
_____ 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
BASIC FUNCTIONS OF THE CIRCULATORY SYSTEM
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Transports _________ from the lungs to body to be used
Transports ______________ and _______________ to the lungs to be removed
Transports _________ from the small intestine to tissues
Fights _____________
Transports _________ from the digestive system to the body and lungs
Carries ________ products (ie: urea) to kidneys for removal in urine
Distributes ____________ from internal source to skin (to get rid of it)
Seals ____________ by forming blood clots
Transports _________ around the body
Maintains _________ in tissues (acts as a buffer with HHb)
Regulates ______________ in tissues (with the Lymphatic system)
ANATOMY OF THE HEART:
The Human Heart has 4 well developed chambers:
1. ______________________
2. ______________________
3. ______________________
4. ______________________
The ________ of the heart pumps _____ blood to the lungs. ________________
The ________ of the heart pumps _____ blood to the body. ________________
1. The Atria are the ___________________ chambers.
a. The Right Atrium receives _______________ blood from the body via the anterior &
posterior _____________.
b. The Left Atrium receives ______________blood from the lungs via the
______________.
2. Atrioventricular Valves:
a. Separate the _______ from the __________.
b. They open when the _______________.
c. They prevent the blood from going ____________ when the ventricles
contract.
3. Chordae Tendinae:
a. Tendon-like pieces of tissue
b. They keep the AV valves from __________ when the ventricles contract
4. Papillary Muscle:
a. Hold and support the _______________ tendinae.
5. The ventricles are the _______________ chambers.
HOW DOES THE HEART PUMP THE BLOOD TO THE LUNGS
(pulmonary circulation)?
a. When the right atrium contracts, it pushes the blood through the _______ valve and into
the _____________.
b. When the ___________ __________, BP forces the __________ valve to close.
c. The BP forces _____________________ open & the blood moves into the
______________ _________.
6. At the lungs…
a. The _________________ _________ take the _____ blood to the
lungs.
b. The ________ is removed from the blood and is replaced with ____
c. The ___________ ________ take the _______ blood to the heart.
What carries the oxygen?
The protein ____________ binds the O2 tightly and carries it to the body cells as
__________________!
7. The SEPTUM:
a. A _______________ that ____________ the right side of the heart from the left side.
b. Keeps the deO2 blood from __________ with the O2 blood
HOW DOES THE HEART PUMP THE BLOOD TO THE BODY
(systemic circulation)?
1. When the left atrium contracts, it pushes the blood
through the ___________ and into the ______________.
2. When the __________ ____________ contracts, the
__________________ is forced closed.
3. Blood is forced through the ________________ and
enters the ________.
4. The left ventricle has a THICKER muscle layer. WHY?
8. The Aorta: there are two parts
a. The ____________ ______________, which splits to take blood to three different
parts in the upper body:
i. The head via the ____________ artery
ii. The arms and lungs via the ___________ arteries
iii. The heart itself via the _____________ artery.
b. The ____________ aorta
The aorta takes O2 blood to the ________.
9. Coronary Arteries and Veins:
a. The ______________ of the aorta take the blood to the ____________________.
b. Takes blood into the ______________ itself. The coronary veins return the deO2 blood
to the ________  right atrium.
10. Vena Cava:
a. These are the ___________ VEINS!
b. They bring the ________ blood back to the heart so that it can be pumped to the lungs.
EXTERIOR VIEW OF THE HEART:
INTERNAL VIEW OF THE HEART:
CONTROL OF HEART FUNCTION:
Why can a heart keep beating outside of the body?
Coordination of Beating:
Heart cells naturally beat slowly if ______ is present
If there was _____ ________________, the heart cells
would all beat ___________
How does the heart work to pump the
blood?
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There are two spots of _______________ in the
heart.
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Both are located in the _______________.
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Nodal tissue is unique: made of specialized _________ ________ combined with
______________.
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It has the ability to ________ independent of other stimuli.
The SA (sinoatrial) NODE:
 This node is found along the wall of the ______ atrium chamber.
 It fires on average, every _____ seconds (or 72 times per minute).
 It stimulates the simultaneous __________ ____________.
 It also sends a nerve impulse along a nerve trunk called the BUNDLE OF HIS to the
__________.
The SA node ___________________________ and has been given the nickname of the
“_________________”
THE AV (atrioventricular) NODE:
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In the ______________ close to the ____ (tricuspid) _____
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When the AV node receives the impulse from the SA node, it fires to initiate the
___________________________ __________________
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The AV node sends its message through the _________, which cause ventricles to
contract.
The pacemaker cells…
Atria beat from ____________, then pause, and the ventricles beat from ____________. WHY?
EKG (electrocardiogram)
There are two parts to the contraction of the heart. The heart beat is a double sound ________
________ .
An ________________________ registers the
voltage changes across the surface of the heart as
it beats.
The letters ___________ are the standard labels
used to identify the parts of the EKG.
_____= the simultaneous contraction of the _______ (caused by __________)
_____ = the contraction of the ____________ (caused by ___________ & purkinje fibres)
_____ = the ___________ of the ventricles (preparation for next contraction)
HOW IS THE BRAIN
INVOLVED?
The natural average resting heart rate is
____________________________ .
The ____________ is connected to the brain by
the __________________ (cranial nerve #10).
The regulation of the heartbeat is under the
influence of the _________________________
(not under conscious control).
The part of the brain that governs the speed of the
heart rate is called the _____________________
__________________.
It will speed up or slow down the heart rate when
needed. **Under ________ circumstances, the
heart controls _______________.
PROBLEMS IN THE HEART:
1. Hardening of the Arteries: ___________________________
2. Burst Coronary Artery = ______________ _______________
Before this happens…
1. Heart ____________ surgery
2. Heart ____________
3. Insert an _____________ heart
BLOOD PRESSURE
The ventricles pump approx. _______ of blood each time they contract. The pulse you feel is blood
__________________ as it moves through your ______________.
__________________________ blood pressure when the
_______________________________.
Blood is being forced through the arteries (approx. ___ mmHg)
______________________________: blood pressure as
______________________________.
This is between contractions, and the blood pressure is less (appox
______ mmHg).
Blood pressure is normally measured along the _________________________ of the arm.
A reading of __________ mmHg is normal.
HIGH BLOOD PRESSURE: ___________________ (ie:
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150/100)
High Blood Pressure puts constant strain on the tissues (especially the capillary beds).
May cause ________________ to burst
If this happens in the brain = a __________. If it happens in the heart = ______________!
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.
LOW BLOOD PRESSURE: _____________________ (ie:
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100/60)
Low blood pressure is not particularly a good thing either.
It can result from:
Genetics
Anemia (low iron levels)
Dehydration
Blood loss
Shock
Proper ___________________ can only be maintained if there is sufficient pressure for
filtration.
What Factors Affect Blood Pressure?
1. __________________:
Bigger (dilate) = lower BP
Smaller (constrict) = higher BP
2. __________________:
Thick blood (little water) = higher BP
Thin (lots of water) = lower BP
3. ____________________:
More fat = higher BP
Thinner = lower BP
4. ______________: affected by plaques (fatty deposits).
Elastic vessels = lower BP
Hardened vessels = high BP
5. ______________: sweating versus water retention
Sweat a lot
Eat lots of salt
= less volume/water
= more volume/water stays in body
= lower BP
= higher BP
6. _______________:
Heart beats faster = higher BP
Heart beats slower = lower BP
7. ___________: as you get older, there is a loss of elasticity in the blood vessels.
Young = very elastic = low BP
Old = not elastic = high BP
8. ____________: constricts blood vessels which means increased pressure to move the blood.
Stressed = constricted vessels
Calm = normal vessels
= Higher BP
= Lower BP