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Anatomy & Physiology
Cardiovascular System
2009
Study Guide
Name_____________________________
Date_____________ Period______
Cardiovascular System Study Guide
Ch. 12 – The Heart
1.
Describe the functions of the heart:
Generate blood pressure-via ventricular contraction
Assist in transport of blood- nutrients to the body
Guarantee one-way flow of blood-valves
Regulates blood supply-extrinsic and intrinsic control
Describe the destination of blood that is
a. Pumped from the left side of the
heart: Systemic circulation
b. Pumped from the right side of the
heart: pulmonary circulation
2. Describe the location of the heart:
Location
In the thoracic cavity
Forms mediastinum (“middle wall”)
with trachea, esophagus, and other
structures
Base is deep to 2nd intercostal space
Apex is deep to 5th intercostal space
3. Describe the shape of the heart:
Like a blunted cone with “tip” (apex)
pointed anteriorly and to the left; most
inferior part of heart
Base (large, flat portion) is superior and
posterior
4.
Describe the composition, location, and
function of the following:
Structure
Pericardial cavity
Pericardial fluid
Pericardium
Ch. 12 – The Heart
Composition
space surrounding
heart
fluid produced by
serous pericardium;
Double-layered,
closed sac
Location
Surrounds heart
with mediastinum
Surrounding heart
between visceral
and parietal
pericardium
Surrounds heart
Function
Provides a space
for the heart
reduces friction of
heart inside
pericardial sac
anchors heart
within
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Anatomy & Physiology
Cardiovascular System
2009
Study Guide
tough, fibrous
connective tissue
Outer layer of
pericardium
Parietal pericardium
– thin, connective
tissue consisting of
epithelium
lines the fibrous
pericardium
Visceral pericardium/
epicardium
– thin, connective
covers the heart
tissue consisting of  These two layers
epithelium
are continuous
with one another
where large
vessels enter/leave
the heart
Fibrous pericardium
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
mediastinum
protection
Decrease friction
---
Describe the causes and symptoms of:
a. Pericarditis
Inflammation of the pericardium
What chambers of the heart receive blood from veins?
right atrium-systemic & left atrium-pulmonary
What chambers of the heart are known as pumping chambers?
ventricles
List the vessels that carry blood to the heart:
Veins-pulmonary & systemic
List the vessels that carry blood away from the heart:
arteries
What is the name of the blood vessels that take deoxygenated blood from the right
ventricle to the lungs?
pulmonary arteries
What is the name of the blood vessels that take oxygenated blood from the lungs to
the left atrium?
pulmonary veins
The valve between the right atrium and the right ventricle is known as the
______Tricuspid _____. The valve between the left atrium and the left ventricle is
known as the _____________Bicuspid_(mitral)__________.
The valves between the ventricles and blood vessels are known as the
_____________semilunar valves______.
Complete flow of blood through the heart.
a. Blood entering the __right___atrium flows through the tricuspid valve and into
the ____right ventricle_______. From there, the deoxygenated blood flows
past the ____pulmonary semilunar ____ valve and into enters the lungs.
b. Oxygenated blood leaves the lungs through the __pulmonary veins__ and
enters the __left__ atrium of the heart. Blood continues to flow through the
__Bicuspid_____ valve and into the __left_ ventricle. From there, blood will
flow past the aortic semilunar valve and into the _____aorta____.
Ch. 12 – The Heart
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Anatomy & Physiology
Cardiovascular System
2009
Study Guide
15. What is the coronary sinus?
The junction of the coronary veins where they enter the right atrium
16. What is the coronary sulcus?
An indentation around the heart which divides the atria from the ventricles
17. Compare coronary arteries with coronary veins:
Coronary arteries deliver oxygen and nutrients to the heart while the
veins remove CO2 and waste from the heart muscle.
18. Explain how the chordae tendinae and papillary muscles work with the
atrioventricular valves:
The Chordae tendenae attach the papillary muscles to the AV valves.
The papillary muscles contract during ventricular contraction to prevent blood to
flow from the ventricles back into the atria.
19. Describe the composition and function of the skeleton of the heart:
The skeleton of the heart is a plate of fibrous connective
tissue; rings around atrioventricular and semilunar valves
1. provide support
2. electrical insulation between atria and ventricles
3. rigid site of attachment for cardiac muscle
20. Describe the characteristics of cardiac muscle:
i.
Cardiac muscle cells are long, branched, and contain 1-2 nuclei
ii.
Sarcomeres contain actin & myosin myofilaments forming
myofibrils and are responsible for striated appearance &
muscle contraction
iii.
Intercalated disks (“insertion between two others”) join adjacent
cells and contain gap junctions which improve action potential
passage between the cells (smooth communication, smooth
contractions)
21. What is the pacemaker of the heart?
i.
SA node-the pacemaker of the heart; in superior wall of right atrium
What is the back-up pacemaker of the heart?
ii.
The AV node can take over the function of the SA node, but results in
an ectopic beat (much slower)
22. Compare the SA and AV nodes:
SA node initiates contraction of the atria and sends electrical signals
to intiate the AV node. The AV node initiates contraction of the ventricles
23. Describe the heart’s conduction system using the following terms:
SA node, AV node, action potentials, atrioventricular bundle, bundle branches,
Purkinje fibers
i.APs originate in SA node and spread through right & left atria,
causing contractions
ii.Atrioventricular (AV) node – in lower part of right atrium
1.
Receives APs from SA node, passing them slowly
through the atrioventricular bundle (specialized cardiac muscle)
Ch. 12 – The Heart
Page 3 of 8
Anatomy & Physiology
Cardiovascular System
2009
Study Guide
a. Slow passage of APs through here allows atria to completely
contract before ventricles begin to
iii.Left and right bundle branches receive APs from AV bundle and send
to Purkinje fibers
1.
Purkinje fibers go to apex & then through ventricle
muscle
iv.New APs aren’t initiated in SA node until ventricles completely relax
24. What is an ectopic beat and how does it happen?
i. The AV node can take over the function of the SA node, but results in an
ectopic beat (much slower)
25. What is fibrillation and how does it happen?
i. Fibrillation – very rapid contraction of cardiac muscle fibers, but not of the
muscle as a whole, resulting in dramatically reduced pumping action of
the heart
26. What is systole?
i. Ventricular systole – contraction of ventricles force AV valves to close,
force semilunar valves open, effects blood into pulmonary trunk & aorta.
Meanwhile, atrial diastole (relaxed) allows atria to fill with blood.
27. What is diastole?
i. Ventricular diastole – ventricles relax causing semilunar
valves to close, allow the AV valves to open and blood to run from atria
into ventricles (to ~70% capacity).
28. What causes the lubb sound?
a. First Heart Sound (“lubb”)
i. lower pitch than 2nd heart sound
ii.
beginning of ventricular systole when AV valves close
1. complete ventricular systole occurs between 1st & 2nd heart sounds
25. What causes the dupp sound?
i. higher pitch than 1st heart sound
ii. beginning of ventricular diastole (SL valves close)
1. complete ventricular diastole occurs between 2nd heart sound & next 1st
heart sound
2. takes longer than systole, thus less time between 1st & 2nd heart sounds
than between 2nd & 1st
29. What is the stroke volume?
i. Stroke volume (SV) – volume of blood pumped/ventricle/contraction
26. What is the heart rate?
i. Heart rate (HR) – number of heart contractions/min
30. What is cardiac output?
 A measure of the hearts ability to pump blood
 CO= SV x HR
31. What vessel is responsible for gas and nutrient exchange with each of the body’s
cells? capillaries
32. Using the graph to the right, explain what ionic changes cause the electrical activities in
cardiac muscle tissue.
Ch. 12 – The Heart
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Anatomy & Physiology
Cardiovascular System
2009
Study Guide
AP series of events:
1.
Depolarization phase- muscle contraction
2. Early repolarization – muscle getting ready
3. Final repolarization phase
33. What is the refractory period?
i.Refractory period – “relaxation” phase caused by plateau phase
1. Muscle fibers relax before contracting again
2. Prevents tetanic contractions (helps maintain rhythmic contractions)
34. Using the graph to the right, describe the electrical activity and physical activity
that corresponds with each peak:
a. Electrocardiogram
1. P wave – caused by depolarization of atrial myocardium (cardiac
muscle)=Atrial contraction
2. QRS complex – caused by depolarization of ventricles=Ventricle
contraction
3. T wave – caused by repolarization of ventricles=Ventricular relaxation
35. Compare bradycardia and tachycardia:
bradycardia- heart rate less than 60bpm
tachycardia- heart rate is greater than 100bpm
36. What’s the difference between intrinsic and extrinsic regulation of the heart:
intrinsic -Mechanisms controlled within the heart itself
extrinsic- Mechanisms controlled outside of the heart
37. Explain how the heart is intrinsically regulated:
 Cardiac muscle contraction force correlates with degree of stretch of
its fibers (the more stretched they become, the more forcefully they
contract)
o Determined by the volume of blood in ventricles at end of
diastole
a. What is Starling’s law of the heart?
i. Venous return – amount of blood returning to heart
1.
With increased preload, cardiac muscle fibers
contract more forcefully, thus more blood ejected, thus increased
stroke volume
2.
With greater venous return, higher preload, higher
CO & vice versa – Starling’s law of the heart
b. Compare right and left heart failure:
1. Right heart failure – backing up of blood in systemic vessels
(edema in legs & feet)
2. Left heart failure – backing up of blood in pulmonary veins (edema
in lungs)
38. Explain how the heart is extrinsically regulated:
i.Autonomic Nervous System – sympathetic & parasympathetic nerves
innervate the heart, affecting the SA node
1. Sympathetic nerve stimulation – increases HR & SV-fight or flight
response
Ch. 12 – The Heart
Page 5 of 8
Anatomy & Physiology
Cardiovascular System
2009
Study Guide
2. Parasympathetic nerve stimulation – decreases HR & SV- rest & digest
3.
ii.Baroreceptors – stretch receptors which monitor blood pressure in aorta
and internal carotid arteries (carry blood to brain)
iii. Chemoreceptors- detect oxygen levels
b. List the factors that can:
i. Increase heart rate
-Epinephrine & norepinephrine released from adrenal gland increase
the SV & HR
-Excitement, anxiety, and anger increase sympathetic stimulation of
the heart, increasing CO
-Drop in pH (increased CO2) – sympathetic stimulation of heart,
increase HR
-Elevated body temperature increases HR
ii. Decrease cardiac output
-Depression increases parasympathetic stimulation, reducing CO2
reduced body temperature decreases HR, eat, lay down
39. If blood pressure becomes elevated, what events occur to bring it back to normal?
i.Increased blood pressure stimulates baroreceptors
ii.AP frequency increases to medulla oblongata
iii.Cardioregulatory center increases parasympathetic stimulation &
decreases sympathetic stimulation
Cause HR & SV to decrease, thus decreasing BP
Ch. 12 – The Heart
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Anatomy & Physiology
Cardiovascular System
Ch. 12 – The Heart
2009
Study Guide
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Anatomy & Physiology
Cardiovascular System
Ch. 12 – The Heart
2009
Study Guide
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