TRICUSPID
AV valve between the right atrium and right ventricle
MITRAL
AV valve between the left atrium and left ventricle
AORTIC
semilunar valve between the left ventricle and the aorta
PULMONIC
semilunar valve between the right ventricle and the pulmonary artery
FLOW OF BLOOD
1. vena cavae
2. right atrium
3. tricuspid valve
4. right ventricle.
5. pulmonic valve into the pulmonary arteries
6. lungs
7. pulmonary veins
8. left atrium (completing pulmonary circulation)
9. mitral valve
10. left ventricle
11. aortic valve into the a
PULMONARY CIRCULATION
movement of blood from the heart, to the lungs, and back to the heart
SYSTEMIC CIRCULATION
movement of oxygenated blood away from the heart to the body, and return of deoxygenated blood back to the heart
VALVES
When ____________ close, heart sounds are heard.
RIGHT CORONARY ARTERY
supplies blood to the right atrium and ventricle and part of the left ventricle
LEFT ANTERIOR DESCENDING ARTERY
supplies blood to the anterior wall of the left ventricle, interventricular septum, right bundle branch, and left anterior fasciculus of the left bundle branch
CIRCUMFLEX ARTERY
supplies blood to the lateral walls of the left ventricle, left atrium, and left posterior fasciculus of the left bundle branch
CARDIAC VEINS
collect blood from the capillaries of the myocardium
CORONARY SINUS
returns blood to the right atrium
ARTERIAL KICK
atrial contraction, contributing about 30% of the cardiac output
CARDIAC OUTPUT
the amount of blood the heart pumps in 1 minute, calculated by multiplying heart rate times stroke volume
STROKE VOLUME
the amount of blood ejected with each ventricular contraction (it's affected by preload, afterload, and contractility)
PRELOAD
the passive stretching exerted by blood on the ventricular muscle at the end of diastole
AFTERLOAD
the amount of pressure the left ventricle must work against to pump blood into the aorta
CONTRACTILITY
the ability of the heart muscle cells to contract after depolarization
1. SYMPATHETIC NERVOUS SYSTEM
2. PARASYMPATHETIC NERVOUS SYSTEM
Two branches of the autonomic nervous system supply the heart:
SYMPATHETIC NERVOUS SYSTEM
increases heart rate, automaticity, AV conduction, and contractility through release of norepinephrine and epinephrine
PARASYMPATHETIC NERVOUS SYSTEM
vagus nerve stimulation reduces heart rate and AV conduction through release of acetylcholine.
AUTOMACITY
a cell's ability to spontaneously initiate an impulse, such as found in pacemaker cells
EXCITABILITY
how well a cell responds to an electrical stimulus
CONDUCIVITY
the ability of a cell to transmit an electrical impulse to another cardiac cell
CONTRACTILITY
how well the cell contracts after receiving a stimulus
PHASE 0
Rapid depolarization � the cell receives an impulse from a nearby cell and is depolarized
PHASE 1
Early repolarization � early rapid repolarization occurs
PHASE 2
Plateau phase � a period of slow repolarization occurs
PHASE 3
Rapid repolarization � the cell returns to its original state
PHASE 4
Resting phase � the cell rests and readies itself for another stimulus.
1. SA NODE
2. INTERNODAL TRACTS
3. BACHMAN'S BUNDLE
4. AV NODE
The electrical impulse begins in the _____ _______________ and travels through the ________________ __________ and _________________'s ____________ to the ____ _______________.
1. AV NODE
2. BUNDLE OF HIS
3. BUNDLE BRANCHES
4. PURKINJE FIBERS
From the ______ ___________, the impulse travels down the _______________ _____ __________, along the ________________ ______________, and through the ______________ ______________.
SA NODE
INTRINSIC FIRING RATE
60 to 100/minute
AV NODE
INTRINSIC FIRING RATE
40 to 60/minute
PURKINJE FIBERS
INTRINSIC FIRING RATE
20 to 40/minute
AUTOMACITY
the ability of a cardiac cell to initiate an impulse on its own
RETROGRADE CONDUCTION
impulses that are transmitted backward toward the atria
REENTRY
when an impulse follows a circular, rather than the normal, conduction path
Answer: A. Automaticity, the ability of a cell to initiate an impulse on its own, is a unique characteristic of cardiac cells.
The term automacity refers to a cell's ability to:
A. initiate an impulse on its own.
B. send impulses in all directions.
C. block impulses formed in areas other than the SA node.
D. generate an impulse when stimulated.
Answer: C. Parasympathetic stimulation of the vagus nerve causes a decrease in heart rate and slowed AV conduction.
Parasympathetic stimulation of the heart results in:
A. increased heart rate and decreased contractility.
B. increased heart rate and faster AV conduction.
C. decreased heart rate and slower AV conduction.
D. decreased heart rate and increased contractili
Answer: A. The SA node is the normal pacemaker of the heart, firing at an intrinsic rate of 60 to 100 times per minute.
The normal pacemaker of the heart:
A. SA node.
B. AV node.
C. bundle of His.
D. Purkinjefibers.
Answer: B. The 0.04-second delay allows the atria to contract and the ventricles to completely fill, which optimizes cardiac out- put.
The impulse delay produced by the AV node allows the atria to:
A. repolarize simultaneously.
B. contract before the ventricles.
C. send impulses to the bundle of His.
D. complete their filling.
Answer: D. The coronary arteries fill with blood when the ventricles are in diastole and filling with blood. The aortic valve is closed at that time, so it no longer blocks blood flow through the coronary ostium into the coronary arteries.
The coronary arteries fill with blood during:
A. atrialsystole.
B. atrialdiastole.
C. ventricularsystole.
D. ventriculardiastole.
Answer: B. Baroreceptors, when stimulated, cause the heart rate to decrease.
When stimulated, baroreceptors cause the heart rate to:
A. increase.
B. decrease.
C. stay the same.
D. becomeirregular.
Answer: B. The pulmonic and aortic valves are semilunar.
The two valves called the semilunar valves are the:
A. pulmonic and tricuspid valves.
B. pulmonic and aortic valves.
C. aortic and mitral valves.
D. aortic and tricuspid valves.
Answer: A. Preload is the passive stretching exerted by blood on the ventricular muscle at the end of diastole. It increases with an increase in venous return to the heart.
8. Passive stretching exerted by blood on the ventricular muscle at the end of diastole is referred to as:
A. preload.
B. afterload.
C. the atrial kick.
D. cardiac output.
Answer: D. If the SA node (which fires at a rate of 60 to 100 times per minute) and the AV node (which takes over firing at 40 to 60 times per minute) are damaged, the Purkinje fibers take over firing at a rate of 20 to 40 times per minute.
A patient admitted with an acute MI has a heart rate of 36 beats/minute. Based on this finding, which area of the heart is most likely serving as the pacemaker?
A. SAnode
B. AVnode
C. Bachmann's bundle
D. Purkinje fibers
MEDIASTINUM
The part of the chest where the heart is located
1. HORIZONTALLY
2. FOURTH
The heart of an infant is positioned more __________________ in the chest cavity than that of the adult. As a result, the apex is at the ____________ left intercostal space.
PERICARDIAL EFFUSION
a condition that compromises the heart's ability to pump blood characterized by excess pericardial fluid
1. SMALLER
As a person ages, his heart usually becomes slightly _______________ and loses its contractile strength and efficiency (although exceptions occur in people with hypertension or heart disease).
70
By age __________, cardiac output at rest has diminished by 30% to 35% in many people.
SYSTOLES
As the myocardium of the aging heart becomes more irritable, extra __________________ may occur, along with sinus arrhythmias and sinus bradycardias. In addition, increased fibrous tissue infiltrates the sinoatrial node and internodal atrial tracts, which
1. ARRYTHMIAS
2. BRADYCARDIA
3. FIBRILLATION
4. FLUTTER
4 PROBLEMS THAT COME WITH AN AGING HEART
VALVES
they prevent backflow, or regurgitation, of blood from one chamber to another.
BETWEEN ATRIUM AND VENTRICLES
location of AV valves
LEAFLETS
The mitral valve has two cusps, or ______________, and the tricuspid valve has three.
COLLATERAL CIRCULATION
This network of smaller arteries that provides blood to capillaries that directly feed the heart muscle.
CORONARY SINUS
The cardiac veins join to form an enlarged vessel called the ____________________ ___________, which returns blood to the right atrium, where it continues through the circulation.
1 MINUTE
On average, it takes a red blood cell less than ____ ____________________ to travel from the heart to the capillaries and back again.
JUNCTIONAL TISSUE
the tissue surrounding nodal tissue that contains pacemaker cells
RE-ENTRY EVENTS
Sometimes impulses cause depolarization twice in a row at a faster-than-normal rate. Such events are referred to as _______________ ______________.
TRIGGERED ACTIVITY
Partial depolarization can lead to spontaneous or secondary depolarization, which involves repetitive ectopic firings called _________________ ___________.
...
Name and identify the layers of the pericardium and its major space or cavity.
...
Name & identify the major coronary arteries and identify related are of heart muscle
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Define the right heart and left heart and the primary functions of each with respect to the pulmonary and systemic circulation
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Define Systole & Diastole
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Describe the process of cardiac filling
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Describe valve function
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Define the term cardiac output & discuss its determinants