apical pulse
caused by the apex of the beating heart contracting the chest wall
fibrous pericardium
double-walled sac that surrounds the heart; the outermost layer; resposible for protection, anchors surrounding structures, prevents over-filling
serous pericardium
deep to the fibrous pericardium; slippery, thin, 2-layer serous membrane
epicardium
most visceral layer of the heart and also an interal part of the heart wall
myocardium
composed mainly of cardiac muscle & forms the bulk of the heart; fibrous skeleton of the heart
endocardium
glistening white sheet of endothelium (squamous epithelium) resting on a thin connective tissue layer; lines the heart chambers & covers the fibrous skeleton of the valves
atria
receiving chamber of the heart
right atrium veins
blood enters the atrium via three veins:
Superior vena cava
Inferior vena cava
Coronary SInus
ventricles
discharging chambers of the heart
pulmonary trunk
right ventricle pumps blood into this
aorta
largest artery in the body; left ventricle ejects blood through this
pulmonary circuit
serves as gas exchange; served by the right ventricle; short-low pressure circulation
systemic circuit
associated with the left ventricle; blood vessels that carry functional blood supply to & from all body tissues; encounters 5 times as much friction (reisitanace) to blood flow
pulmonary circuit pump
right side of the heart
systemic circuit pump
left side of the heart
coronary circulation
functional blood supply of the heart; shortest circulation in the body; provided by right & left coronary arteries
left coronary arteries
Anterior intraventricular artery & circumflex artery
right coronary arteries
Right marginal artery & Posterior interventricular artery
coronary sinus
joined together with the cardiac veins to form this which has three large tributaries: Great, middle, & small cardiac veins
tricuspid valve
has 3 flexible cusps
mitral valve
AKA bicupsid valve; has 2 flaps
semilunar valves
aortic & pulmonary valves; prevent backflow into the assoiciated ventricles
chordae tendinae
heart strings"; anchor the cusps to the papillary muscle protruding from the ventricular wall
absolute refractory period
the excitable period when sodium channels are still open or activated
sinoatrial node
SA node"; the "pacemaker" of the intrinsic conduction system. Characteristic rhythm called sinus rhythm.
atrioventricular node
AV node"; where the impulse pauses in the intrinisic conduction system
AV bundle
connects the atria to the ventricles in the intrinisic conduction system
right & left bundle branches
conduct the impulses through the intraventricular septum
Purkinje fibers
depolarize the contractile cells of both ventricles
ECG
electrocardiography; composite of all the action potentials generated by nodal & contracile cells at a given time
P wave
lasts about 0.08 seconds & results from movement of the depolartixation wave from the SA node through the atria
QRS
complex that results from ventricular depolartization & proceeds ventricular contraction; average duration is 0.08 seconds
T wave
caused by ventricular repolarization & typically lasts 0.16 seconds
P-Q interval
the time (about 0.16 seconds) from the beginning of atrial excitation to the beginning of ventricular excitation
S-T segment
the action potential of the ventricular myocytes are in their plateau phases; the entire ventricular myocardium is depolarized
Q-T interval
lasts 0.38 seconds; period from the beginning of ventricular depolarization through ventricular repolarization
systole
contraction
diastole
relaxation
cardiac output
the amount of blood pumped out by each ventricle in 1 minute
stroke volume
the volume of blood by one ventricle with each beat
end diastolic volume
EDV; the amount of blood that collects in a ventricle during diastole
end systolic volume
ESV; the volume of blood remaining in a ventricle after it has contracted
preload
the degree to which cadiac muscle cells are stretched just before they contract. Controls stroke volume.
contractility
the contactile strength achieved at a given muscle length. rises when there is more Ca2+
positive inotropic agents
factors that increase contractility
negative inotropic agents
factors that decrease or impair contractility
afterload
the pressure that must be overcome for the ventricles to eject blood
pericarditis
inflammation of the pericardium; roughens the serous membrane surfaces
angina pectoris
thoracic pain caused by fleeting deficiency of blood delivery to the myocardium
mycardial infarction
MI" or "heartattack"; caused by prolonged coronary blockage
incompetent valve
forces the heart to pump the same blood over & over because the valve does not close properly & blood backflows
valvular stenosis
narrowing"; valve flaps become stiff & constrict the opening
arrythmias
defects in the intrinisc conduction system causing irregular heart rhythms
fibrillation
a condition of rapid & irregular or out-of-phase contractions in which control of heart rhythm is taken from the SA node by rapid activity in other heart regions
heart murmurs
abnormal heart sounds; most often indicate heart valve problems
tachycardia
abnormally fast heart rate (more than 100 beat per minute) that may result from elevated body temperature, stress, certain drugs, or heart disease
bradycardia
heart rate slower that 60 beats/minute; may result from low body temperature, certain drugs, or parasympathetic nervous activation
congenital heart defects
most common of all birth defects and include: Septal defects, Patent ductus arteriosus, co arctation of the aorta, & Tetralogy of Fallot
interatrial septum
separates the two atria
interventricular septum
separates the two ventricles
intercalated discs
junctions between cells; anchor cardiac cells
gap junctions
allows ions to pass; electrically couple adjacent cells
desomosomes
prevent cells from separating during contraction
positive chrontropic factors
increase heart rate
negative chrontropic factors
decrease heart rate
congestive heart failure
progressive condition where the cardiac output is so low that blood circulation is inadequate to meet tissue needs
embryonic heart chambers
Sinus venous, atrium, ventricle, & bulbus cordis
Cardiac Output is
A. the number of times the heart beats in one minute.
B. the number of impulses fired by the SA node in one minute.
C. the amount of blood pumped out of each ventricle in one minute.
D. the amount of blood filling each ventricle at the e
C. the amount of blood pumped out of each ventricle in one minute.
Choose the correct sequence of current flow through the heart wall.
A. SA node, Purkinje fibers, AV node, AV bundle of His, right and left bundle branches
B. SA node, AV node, AV bundle of His, right and left bundle branches, Purkinje fibers
C. Purkinje f
B. SA node, AV node, AV bundle of His, right and left bundle branches, Purkinje fibers
During pulmonary circulation blood leaves the
A. right ventricle and moves to the lungs.
B. right atrium and goes directly to the left ventricle.
C. left ventricle and moves to the lungs.
D. right ventricle and goes directly to the aorta.
E. right atrium
A. right ventricle and moves to the lungs.
During systemic circulation, blood leaves the
A. left ventricle and goes directly to the aorta.
B. right atrium and goes directly to the lungs.
C. lungs and moves to the left atrium.
D. right ventricle and goes directly to the aorta.
E. right ventricle an
A. left ventricle and goes directly to the aorta.
During the spike of an action potential in a cardiac muscle cell
A. Ca2+ moves out of the cell into the extracellular fluid.
B. K+ channels open to let K+ move into the cell.
C. both Na+ and Ca2+ move into the cell at the same time.
D. there is a rapid in
D. there is a rapid influx of Na+ into the cell.
Identify the correct sequence of blood flow through the chambers of the heart.
A. Lungs, right ventricle, left ventricle, right atrium, left atrium
B. Left atrium, left ventricle, right ventricle, right atrium, and lungs
C. Right atrium, right ventricle,
C. Right atrium, right ventricle, lungs, left atrium, left ventricle
The absolute refractory period refers to the time during which
A. the muscle cell is NOT in a position to respond to a stimulus of any strength.
B. the muscle cell is ready to respond to a threshold stimulus.
C. a cardiac muscle cannot respond to any stim
A. the muscle cell is NOT in a position to respond to a stimulus of any strength.
The cardiac cycle includes all of the following events EXCEPT
A. the changes in pressure gradients in all chambers of the heart.
B. the closing and opening of the heart valves during each heart beat.
C. the number of times the heart beats in one minute.
D
C. the number of times the heart beats in one minute.
The coronary arteries arise from the
A. pulmonary trunk.
B. superior vena cava.
C. inferior vena cava.
D. aorta.
E. right atrium.
D. aorta.
The endocardium is composed of
A. stratified squamous epithelium.
B. simple squamous epithelium.
C. simple columnar epithelium.
D. cardiac muscle cells.
E. simple cuboidal epithelium
B. simple squamous epithelium.
The inferior vena cava brings blood from the lower regions of the body and empties into the
A. left atrium.
B. right atrium.
C. left ventricle.
D. right ventricle.
E. Aorta.
B. right atrium.
The inner lining of the fibrous pericardium is formed by the
A. parietal layer of serous pericardium.
B. endocardium.
C. epicardium.
D. myocardium.
E. diaphragm.
F. pericardial cavity.
A. parietal layer of serous pericardium.
The interventricular septum forms a dividing wall between the
A. left atrium and right atrium.
B. right ventricle and left atrium.
C. left and right ventricles.
D. left atrium and left ventricle.
E. right atrium and right ventricle
C. left and right ventricles
The P-wave is a measure of
A. atrial repolarization.
B. ventricular depolarization.
C. ventricular hyperpolarization.
D. ventricular contraction.
E. atrial depolarization.
E. atrial depolarization.
The pacemaker of the heart is the
A. SA node.
B. the bundle branches.
C. AV node.
D. Bundle of His.
E. Purkinje fibers.
A. SA node
The tricuspid valve is located between the
A. right and left atria.
B. right atrium and right ventricle.
C. left atrium and left ventricle.
D. right and left ventricles.
E. right ventricle and the aorta
B. right atrium and right ventricle.
When the mitral valve closes, it prevents the backflow of blood from the
A. left ventricle into the left atrium.
B. right atrium into the right ventricle.
C. left atrium into the left ventricle.
D. left ventricle into the aorta.
E. right ventricle into th
A. left ventricle into the left atrium.
Which is the correct sequence of layers in the heart wall, starting with the outer layer?
A. Epicardium, myocardium, endocardium
B. Endocardium, smooth muscle, epicardium
C. Endocardium, epicardium, myocardium
D. Parietal pericardium, myocardium, endocard
A. Epicardium, myocardium, endocardium
Which of the following statements is NOT true about the shape, position and location of the heart?
A. The heart is located between the two lungs within the mediastinum.
B. Approximately two-thirds of the heart is found to the left of the midline.
C. The h
D. The heart is enclosed in a double-layered sac called the pleural membrane.
Which statement about the extrinsic innervation of the heart is NOT true?
A. Parasympathetic nerve stimulation reduces the heartbeat.
B. Sympathetic impulses travel through the vagus nerve.
C. Sympathetic nerve stimulation of the heart increases the rate
B. Sympathetic impulses travel through the vagus nerve.
The vessels that carry oxygen to the myocardial cells are called
A. pulmonary arteries.
B. aortic arteries.
C. coronary veins.
D. coronary arteries.
E. pulmonary veins
D. coronary arteries.
The cells of the myocardium behave as a single coordinated unit called a
A. functional syncytium.
B. cardiac cycle.
C. sarcomere.
D. contractile unit.
E. pacemaker
A. functional syncytium.
The ability of some cardiac muscle cells to initiate their own depolarization and cause depolarization of the rest of the heart is called
A. an action potential.
B. automaticity.
C. fibrillation.
D. a functional syncytium.
E. absolute refractory period
B. automaticity.
Guided by powerful signaling molecules, the human heart develops from
A. ectoderm and endoderm.
B. ectoderm.
C. endoderm.
D. blood cells.
E. mesoderm.
E. mesoderm.
Which of the following is an age-related change of the heart that affects function?
A. Fibrosis of cardiac muscle
B. Stretching of myocardium due to overuse
C. Increase in cardiac reserve
D. Loss of elasticity of cardiac muscle
E. Thinning of the valve fl
A. Fibrosis of cardiac muscle
Which of the following vessels is most likely to supply the anterior left ventricular myocardium?
A. Circumflex artery
B. Posterior interventricular artery
C. Marginal artery
D. Left anterior descending artery
E. Right coronary artery
D. Left anterior descending artery
Which of the following drains blood DIRECTLY from the myocardium?
A. Coronary sinus
B. SVC
C. Right coronary artery
D. Middle cardiac vein
E. IV
D. Middle cardiac vein
Which of the following is the cause of the "plateau" in cardiac muscle action potentials?
A. Chloride ion outflux
B. Sodium ion influx
C. Potassium ion influx
D. Calcium ion outflux
E. Calcium ion influx
E. Calcium ion influx
Which of the following structures lies on the outside surface of the heart and is an integral part of the cardiac wall?
A. the fibrous pericardium
B. The parietal layer of serous pericardium
C. the pericardial sac
D. the epicardium
D. the epicardium
Which of the following structures is continuous with the inner lining of blood vessels?
A. the endocardium
B. the epicardium
C. the pericardial sac
D. the pectinate muscles
A. the endocardium
The fossa ovalis is located in the
A. ventricle.
B. interatrial septum.
C. interventricular septum.
D. atrium
B. interatrial septum.
The trabeculae carneae are located in the
A. ventricles.
B. endocardium.
C. epicardium.
D. atrium.
A. ventricles.
What part of the heart is considered the systemic circuit pump?
A. the left atrium
B. the left ventricle
C. the right atrium
D. the right ventricle
B. the left ventricle
If the circumflex artery of the heart was blocked, the myocardium in the _________________ would be ischemic.
A. the apex
B. the left atrium and the posterior wall of the left ventricle
C. the lateral aspects of the heart
D. interventricular septum and th
B. the left atrium and the posterior wall of the left ventricle
Attached to the AV valve flaps are the
A. pectinate muscles.
B. chordae tendineae.
C. papillary muscles.
D. trabeculae carneae.
B. chordae tendineae.
Blood spurts back into the _____________ when the right atrium contracts
A. pulmonary trunk
B. pulmonary veins
C. venae cavae
D. aorta
C. venae cavae
Which of the following valves is most often faulty in the heart?
A. the pulmonary semilunar valve
B. the aortic semilunar valve
C. the mitral or bicuspid valve
D. the tricuspid valve
C. the mitral or bicuspid valve
The myocardium functions as a functional syncytium due to
A. branching of myocardial cells.
B. the presence of striations in the myocardium.
C. the presence of desmosomes.
D. the presence of gap junctions.
D. the presence of gap junctions.
Which of the following factors gives the myocardium its high resistance to fatigue?
A. the coronary circulation
B. a very large number of mitochondrion in the cytoplasm
C. the presence of intercalated discs
D. gap junctions
B. a very large number of mitochondrion in the cytoplasm
All but which of the following statements about autorhythmic myocardial cells are correct?
A. They have special ion channels in their sarcolemma.
B. They do not maintain a stable resting membrane potential.
C. They are the first myocardial cells to contra
C. They are the first myocardial cells to contract.
Autorhythmic cardiac cells are found in all the following location except the
A. SA node.
B. Purkinje cells.
C. AV node.
D. interatrial septum.
D. interatrial septum.
Which of the following is clinically significant as an ectopic pacemaker of the heart?
A. drinking several cups of caffeinated coffee
B. excessive smoking
C. anxiety
D. extrasystole contractions associated with angina pectoris
D. extrasystole contractions associated with angina pectoris
The _________ nerve carries parasympathetic fibers to the SA node.
A. facial
B. vagus
C. hypoglossal
D. accessory
B. vagus
The cardioacceleratory center fibers are part of the
A. cranial peripheral nervous system.
B. sympathetic nervous system.
C. somatic peripheral nervous system.
D. parasympathetic nervous system
B. sympathetic nervous system.
An enlarged R wave on an ECG would indicate
A. cardiac ischemia.
B. a myocardial infarction.
C. an enlarged ventricle.
D. repolarization abnormalities.
C. an enlarged ventricle.
The pacemaker potential produced in autorhythmic cells is due to the presence of
A. intercalated discs at cell junctions.
B. desmosomes.
C. many large mitochondria in the cytoplasm.
D. a continuously depolarizing membrane that slowly reaches threshold
D. a continuously depolarizing membrane that slowly reaches threshold
Which of the following ions has the greatest affect on the autorhythmic capabilities of the myocardium?
A. K+
B. Cl-
C. Na+
D. Ca2+
D. Ca2+
Which of the following events would cause the gap junctions between cardiac cells to close?
A. atrial fibrillation
B. arrhythmia
C. ischemia
D. premature ventricular contractions (PVCs)
C. ischemia
A doctor puts his stethoscope on a patient's chest over the location of the heart and hears a swishing sound. Which of the following conditions is the best diagnosis for the patient's condition?
A. incompetent cardiac valve
B. angina pectoris
C. cardiac t
A. incompetent cardiac valve
The end diastolic volume is the
A. volume of blood in the ventricle at the end of ventricular relaxation.
B. volume of blood in the atria at the end of atrial relaxation.
C. volume of blood in the atria at the end of atrial contraction.
D. volume of blood
A. volume of blood in the ventricle at the end of ventricular relaxation.
The phase in the cardiac cycle in which the ventricles are completely closed and the volume of blood in them is constant is referred to as the
A. isovolumetric relaxation phase.
B. quiescent period.
C. isovolumetric contraction phase.
D. ventricular eject
C. isovolumetric contraction phase.
The dicrotic notch observed on tracing of blood pressure recording is due to
A. pulmonary semilunar valve closure.
B. mitral valve closure.
C. tricuspid valve closure.
D. aortic semilunar valve closure.
D. aortic semilunar valve closure
Positive inotropic agents
A. cause hemolysis of blood clots.
B. increase the contractility of the heart.
C. decrease the contractility of the heart.
D. prevent blood clotting.
B. increase the contractility of the heart.
EXTRA CRED TERM asystole
situation in which the heart fails to contract
EXTRA CRED TERM cardiac catheteriztion
diagnostic procedure involving passage of a fine catheter through a blood vessel into the heart, blood samples are drawn, allowing oxygen content, blood flow, and pressures within the heart to be measured. Findings help to detect valve problems, heart def
EXTRA CRED TERM commotio cordis
concussion of the heart" situation in which a mild blow to the chest causes heart failure and sudden death because it occurs during a vulnerable interval (2ms) when the heart is repolarizing.
EXTRA CRED TERM cor pulmonale
a condition of right sided heart failure resulting from elevated blood pressure in the pulmonary circuit. Acute cases may develop suddenly due to pulmonary embolism, chronic cases are usually associated with chronic lung conditions
EXTRA CRED TERM endocarditis
inflammation of the endocardium. usually confined to the endocardium of the heart valves. often results from bacterial infection in the bloodstream, but may result from fungal infection or an autoimmune response. Drug addicts may develop from contaminated
EXTRA CRED TERM heart palpatation
a heart beat that is unusually strong, fast, or irregular so that the person is aware of it. may be caused by drugs, emotional pressure, or heart disorders
EXTRA CRED TERM hypertrophic cardiomyopathy (HCM)
the leading cause of sudden death in young athletes, this condition, which is usually inherited, causes the cardiac muscle to enlarge, thickening the heart wall. The heart pumps strongly, but does not relax well during diastole when the heart is filling
EXTRA CRED TERM mitral valve prolapse
Valve disorder affecting up to 1% of the population. most often seen in young women. appears to have genetic basis resulting in abnormal chordae tendinae or a malfunction of the pappillary muscles. one or more of the flaps of the mitral valve become incom
EXTRA CRED TERM myocarditis
inflammation of the cardiac muscle layer of the heart. sometimes follows an untreated streptococcal infection in children. may weaken the heart and impair its ability to act as a pump
EXTRA CRED TERM paroxysmal atrial tachycardia (PAT)
Bursts of atrial contraction with little pause between them
EXTRA CRED TERM Ventricular tachycardio (VT or VTac)
Rapid ventricular contractions that are not coordinated with atrial activity.
true or false; the myocardium receives its blood supply from the coronary arteries.
true
true or false; cardiac muscle has more mitochondria and depends less on a continual supply of oxygen than does skeletal muscle.
false
true or false; anastomoses among coronary arterial branches provide collateral routes for blood delivery to the heart muscle.
true
true or false; tissues damaged by myocardial infarction are replaced by connective tissue
true
true or false; the left side of the heart pumps the same volume of blood as the right
true
true or false; the papillary muscles contract after the other ventricular muscles so that they can take up the slack on the chordae tendineae before the full force of ventricular contractions sends blood against the AV valve flaps.
false
true or false; an ECG provides direct information about valve function.
false
true or false; as pressure in the aorta rises due to atherosclerosis, more ventricular pressure is required to open the aortic valve.
true
true or false; autonomic regulation of heart rate is via two reflex centers found in the pons.
false
Which of the following is not an age-related change affecting the heart?
A. thinning of the valve flaps
B. decline in cardiac reserve
C. fibrosis of cardiac muscle
D. atherosclerosis
A. thinning of the valve flaps
true or false; congestive heart failure means that the pumping efficiency of the heart is depressed so that there is inadequate delivery of blood to body tissues
true
Normal heart sounds are caused by which of the following events?
A. excitation of the SA node
B. closure of the heart valves
C. friction of blood against the chamber walls
D. opening and closing of heart valves
B. closure of the heart valves
Which of the events below does not occur when the semilunar valves are open?
A. ventricles are in diastole
B. blood enters pulmonary arteries and the aorta
C. AV valves are closed
D. ventricles are in systole.
A. ventricles are in diastole
Hemorrhage with a large loss of blood causes...
A. lowering of blood pressure due to change in cardiac output
B. A rise in blood pressure due to change in cardiac output
C. no change in blood pressure, but a slower heart rate
D. no change in blood pressur
A. lowering of blood pressure due to change in cardiac output
The left ventricular wall of the heart is thicker than the right wall in order to...
A. accomodate a greater volume of blood
B. expand the thoracic cage during diastole
C. pump blood with greater pressure
D. pump blood through a smaller valve
C. pump blood with greater pressure
Damage to the __________ is referred to as a heart block.
A. SA node
B. AV valves
C. AV bundle
D. AV node
D. AV node
The P wave of a normal electrocardiogram indicates...
A. ventricular repolarization
B. ventricular depolarization
C. atrial repolarization
D. atrial depolarization
D. atrial depolarization
Blood within the pulmonary veins returns to the...
A. right atrium
B. left atrium
C. right ventricle
D. left ventricle
B. left atrium
Small muscle masses attached to the chordae tendineae are the...
A. trabeculae carneae
B. pectinate muscles
C. papillary muscles
D. vena cava
C. papillary muscles
The term for pain associated with deficient blood delivery to the heart that may be caused by the transient spasm of coronary arteries is...
A. ischemia
B. pericarditis
C. myocardial infarct
D. angina pectoris
D. angina pectoris
To auscultate the aortic semilunar valve, you would place your stethescope in the ...
A. second intercostal space to the right of the sternum
B. second intercostal space to the left of the sternum
C. 5th intercostal space, inferior to the left nipple
D. 5
A. second intercostal space to the right of the sternum
The source of blood carried to capillaries in the myocardium would be the...
A. coronary sinus
B. fossa ovalis
C. coronary arteries
D. coronary veins
C. coronary arteries
If the length of the absolute refractory period in cardiac muscle cells was the same as it is for skeletal muscle cells...
A. it would be much longer before cardiac cells could respond to a second stimulation
B. contractions would last as long as the refr
C. tetanic contractions might occur, which would stop the hearts pumping action.
Norepinephrine acts on the heart by
A. decreasing heart contractility
B. causing a decrease in stroke volume
C. blocking the action of calcium
D. causing threshold to be reached more quickly
D. causing threshold to be reached more quickly
If the vagal nerves to the heart were cut, the result would be that...
A. the heart would stop, the vagal nerves trigger the heart to contract
B. the heart rate would increase about 25 beats per minute
C. the AV node would become the pacemaker of the hear
B. the heart rate would increase about 25 beats per minute
The tricuspid valve is closed when...
A. the ventricle is in diastole
B. the ventricle is systole
C. the atrium is contracting
D. the blood is moving from atrium to ventricle
B. the ventricle is systole
select the correct statement about the heart valves
A. the mitral valve separates the right atrium from the right ventricle
B. the tricuspid valve divides the left atrium from the left ventricle
C. aortic and pulmonary valves control the flow of blood int
D. The AV valves are supported by chordae tendineae so that regurgitation of blood into the atria during ventricular contraction does not occur.
The second heart sound is heard during which phase of the cardiac cycle
A. isovolumetric relaxation
B. isovolumetric contraction
C. ventricular ejection
D. ventricular filling
A. isovolumetric relaxation
The time of day most hazardous for heart attack is...
A. morning
B. noontime
C. evening
D. during sleep
A. morning
If we were able to artificially alter the membrane permeability of pacemaker cells so that sodium influx was more rapid...
A. threshold is reached more quickly and heart rate would increase
B. potassium channels compensate and no change in heart rate woul
A. threshold is reached more quickly and heart rate would increase
Isovolumetric contraction...
A. refers to the short period during ventricular systole when the ventricles are completely closed chambers.
B. occurs while the AV valves are open
C. occurs immediately after the aortic and pulmonary valves close
D. occurs on
A. refers to the short period during ventricular systole when the ventricles are completely closed chambers.
Commotio cordis is heart failure due to a...
A. mild electrical shock to the heart itself
B. severe electrical shock to the body
C. relatively mild blow to the chest that occurs during a vulnerable interval (2ms) when the heart is repolarizing
D. loss of
C. relatively mild blow to the chest that occurs during a vulnerable interval (2ms) when the heart is repolarizing
cardioacceleratory center
located in the medulla oblongata, projects to sympathetic neurons
cardioinhibitory center
located in the medulla oblongata, projects to parasympathetic neurons
cardiac output, how do you calculate CO
HR x SV , amout of blood pumped out by each ventricle per minute
stroke volume, sv
EDV - ESV , volume of blood pumped out by one ventricle during one beat
end diastolic volume
amt of blood that collects in ventricle during diastole
end systolic volume
amt of blood remaining in ventricle. after contaction