Term
What are the three main components of the cardiovascular system? |
|
Definition
- blood
- blood vessels
- heart
|
|
|
Term
What are the three types of blood vessels? |
|
Definition
areteries, veins, and capillaries |
|
|
Term
What are the three types of circulation? |
|
Definition
- pulmonary circulation
- systemic circulation
- lymphatic circulation (system)
|
|
|
Term
What is pulmonary circulation? |
|
Definition
circulation that goes from the heart to the lungs |
|
|
Term
What is systemic circulation? |
|
Definition
circulation that goes from the heart to the rest of the body |
|
|
Term
What three systems is the lymphatic system involved with? |
|
Definition
cardiovascular, immune, and digestive systems |
|
|
Term
What is systolic pressure (mm Hg)? |
|
Definition
the highest arterial blood pressure reached during any given ventricular cycle |
|
|
Term
What is diastolic pressure (mm Hg)? |
|
Definition
the lowest arterial blood pressure reached during any given ventricular cycle |
|
|
Term
What is venous pressure (mm Hg)? |
|
Definition
the pressure exerted on the walls of the veins by the circulating blood |
|
|
Term
What is packed cell volume (%)? |
|
Definition
the ratio of the volume occupied by packed red blood cells to the volume of the whole blood as measured by a hematocrit |
|
|
Term
What is stroke volume (mL)? |
|
Definition
the volume of blood pumped out of one ventricle of the heart in a single beat |
|
|
Term
What other three things are measured with regards to the cardiovascular system? |
|
Definition
- heart rate (per min)
- leukocytes (per micro liter)
- erythrocytes (per micro liter)
|
|
|
Term
What are the four main structures of the heart? |
|
Definition
- atrium
- ventricle
- septum
- myocardium
|
|
|
Term
The sinoatrial (SA) node is also known as the _________ of the heart. |
|
Definition
|
|
Term
What is the sinoatrial node? |
|
Definition
a small specialized region in the right atrial wall in reptiles, birds, and mammals |
|
|
Term
What is the atrioventricular (AV) node? |
|
Definition
a small bundle of specialized cardiac muscle cells located at the base of the right atrium near the septum, just above the junction of the atria and ventricles |
|
|
Term
What is myogenic contraction? |
|
Definition
myocytes contraction that originates from a property of the myocyte itself (ex: the contraction is initiated by the cell itself, not an outside occurance or stimulus such as a nerve innervation |
|
|
Term
What type of muscle in the body exhibits myogenic contraction? |
|
Definition
|
|
Term
What is neurogenic contraction? |
|
Definition
muscle contraction that originates from an external neural stimulus |
|
|
Term
|
Definition
|
|
Term
How did vertebrate systemic hearts evolve? |
|
Definition
they evolved from a two-chambered heart into four-chambered heart |
|
|
Term
Avian and mammalian hearts are _____ pumps. |
|
Definition
|
|
Term
What is the sequence of blood circulation starting with the vena cava? |
|
Definition
- vena cava, right atrium, right ventricle, pulmonary artery, lungs, pulmonary vein, left atrium, left ventricle, aorta, systemic circulation
|
|
|
Term
What are the four main valves in the heart? |
|
Definition
- tricuspid valve
- pulmonary valve
- aortic valve
- mitral valve
|
|
|
Term
Which valve is the right atrioventricular valve? |
|
Definition
|
|
Term
Which valve is the left atrioventricular valve? |
|
Definition
|
|
Term
Why is the wall of the right ventricle so much thinner than the wall of the left ventricle? |
|
Definition
because the left ventricle has to pump blood all throughout the body while the right ventricle only has to pump it to the lungs |
|
|
Term
What is the purpose of heart valves? |
|
Definition
they ensure that blood flows in the proper direction through the heart |
|
|
Term
When pressure behind the valve is greater, it (closes/opens). |
|
Definition
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|
Term
When pressure is greater infront of the valve, it (closes/opens). Why? |
|
Definition
closes; because valves are on;y one-way so they do not open in the opposite direction |
|
|
Term
What is the purpose of atrioventricular valves? |
|
Definition
they prevent backflow of the blood from the ventricles to the atria during ventricular systole (contraction) |
|
|
Term
What are the two atrioventricular valves? |
|
Definition
tricuspid valve and mitral valve |
|
|
Term
Where is the tricuspid valve located? |
|
Definition
between the right atrium and ventricle |
|
|
Term
Where is the mitral valve located? |
|
Definition
between the left ventricle and atrium |
|
|
Term
What is the purpose of the semilunar valves? |
|
Definition
to prevent backflow of blood from the arteries (pulmonary artery and aorta) to the ventriclesduring ventricular diastole |
|
|
Term
What are the two semilunar valves? |
|
Definition
aortic valve and pulmonary valve |
|
|
Term
Where is the aortic valve located? |
|
Definition
between the left ventricle and the aorta |
|
|
Term
Where is the pulmonary valve located? |
|
Definition
between the right ventricle and the pulmonary artery |
|
|
Term
What type of tissue are valves made of? How does this affect the way they work? |
|
Definition
connective tissue (not cardiac muscle tissue); this means that they open and close passively in response to changes in pressure |
|
|
Term
What is ventricular systole? |
|
Definition
|
|
Term
What is ventricular diastole? |
|
Definition
|
|
Term
Cardiac muscle is (unstriated/unstriated) and consists of __________ that is similar to _______ muscle. |
|
Definition
striated, sarcomeres, skeletal |
|
|
Term
How many nuclei does cardiac muscle contain? |
|
Definition
|
|
Term
Cardiac muscle cells contain numerous ___________. They make up up to ___% of the cell volume. |
|
Definition
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|
Term
Adjacent cells are joined end to end at structures called ________ that contain _________. |
|
Definition
intercalated discs, desmosomes |
|
|
Term
What is the function of intercalated discs and desmosomes? |
|
Definition
they act like rivets and hold the cells tightly together where gap junctions permit action potentials to easily spread from one cardiac muscle cell to adjacent cells |
|
|
Term
What are the two types of cardiac muscle cells? |
|
Definition
contractile cells and autorythmic cells |
|
|
Term
Most muscle cells in the heart are _______ cells. |
|
Definition
|
|
Term
What is depolarization in contractile cells like? |
|
Definition
it is very rapid and due to the inward diffusion of sodium |
|
|
Term
What happens during repolarization of contractile cells? |
|
Definition
- it begins with a slow outward diffusion of potassium, but that is largely offset by the slow inward diffusion calcium
- this means that repolarization begins with a plateau phase
- then potassium diffuses out much more rapidly as the calcium channels close, and the membrane potential quickly reaches the resting potential
|
|
|
Term
Autorythmic cells exhibit _______ potentials. |
|
Definition
|
|
Term
What causes depolarization in autorythmic cells? |
|
Definition
it is due to the inward diffusion of calcium, not sodium, as in nerve cells |
|
|
Term
What happens during depolarization of autorythmic cells? |
|
Definition
the slow calcium channels open and then depolarization quickly concludes when the fast calcium channels open |
|
|
Term
What causes repolarization of autorythmic cells? |
|
Definition
the outward diffusion of potassium |
|
|
Term
What parts of the heart are made up of autorythmic cells? |
|
Definition
- sinoatrial node
- atrioventricular node
- atrioventricular bundle
- right and left bundle branches
- purkinje fibers
|
|
|
Term
What is the antriventricular bundle sometimes called? |
|
Definition
|
|
Term
|
Definition
|
|
Term
Autorythmic cells don't have voltage gated ____ channels. |
|
Definition
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|
Term
In autorythmic cells, ____ permeability changes between action potential cycles. |
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
The ____ node exhibits the fastest rate of autorythmicity. |
|
Definition
|
|
Term
How does the heart ensure efficient pumping? |
|
Definition
by coordinating the spread of cardiac excitation |
|
|
Term
What must be complete before the onset of ventricular contraction? |
|
Definition
atrial excitation and contraction |
|
|
Term
The pair of _____ and pair of _____ should be functionall coordinated so that both members of the pair contract ___________. |
|
Definition
atria, ventricles, simultaneously |
|
|
Term
Electrical activity of autorythmic cells begins at the ________ and quickly spreads through ________. |
|
Definition
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|
Term
The electrical activity of autorythmic cells that starts as the SA node then travels through the heart's conducting system which includes moving from the _________ to the ________ to the ________ and then to the ________ through the ventricles. |
|
Definition
AV node, AV bundle, bundle branches, purkinje fibers |
|
|
Term
Different autorythmic cells have different _______. |
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
What part of the heart has the fastest rhythm? What does this result in? |
|
Definition
SA node, which results in it setting the rate of contraction for the entire heart |
|
|
Term
|
Definition
|
|
Term
The action potential of contractile cardiac muscle cells shows a charcateristic _______. |
|
Definition
|
|
Term
What maintains the plateau in contractile cells? |
|
Definition
activation of slow Ca2+ channels and marked decrease in K+ permeability |
|
|
Term
What happens during the rising phase of an action potential in contractile cells? |
|
Definition
the membrane rapidly becomes reversed from -90mV to 30mV by an explosive increase in the Na+ permeability |
|
|
Term
What causes the rapid falling phase of the action potential in contractile cells? |
|
Definition
inactivation of the Ca2+ channels and activation of EAG K+ channels |
|
|
Term
|
Definition
|
|
Term
During electrical activity of the contractile cells, what does Ca2+ entry from the ECF induce? What does this result in? |
|
Definition
a much larger calcium release from the sarcoplasmic reticulum; results in a longer period of cardiac contraction |
|
|
Term
How is tetanus of the cardiac muscle prevented? |
|
Definition
|
|
Term
|
Definition
|
|
Term
What does a long refractory period in the cardiac muscle mean? |
|
Definition
it means that the muscle cannot be stimulated again until contraction is almost over and this makes summation impossible |
|
|
Term
Why is a refractory period in cardiac muscle considered to be an important protective mechanism? |
|
Definition
because pumping requires alternate periods of contraction and relaxation; prolonged tetany would prove fatal |
|
|
Term
In descending order, which four parts of the body recieve the most amount of blood? |
|
Definition
- digestive system
- kidneys
- skeletal muscle
- brain
|
|
|
Term
What does cardiac output depend on? |
|
Definition
heart rate and stroke volume |
|
|
Term
What is the formula for cardiac output? |
|
Definition
cardiac output (vol/min) = heart rate (beats/min) x stroke volume (vol/beat) |
|
|
Term
What is heart rate primarily determined by? |
|
Definition
- antagonistic regulation of autonomic influences on the SA node
|
|
|
Term
What happens in parasympathetic control of the heart? |
|
Definition
- acetylcholine is released which binds to the muscarinic receptor at the SA and AV nodes which are coupled to the inhibitory G protein
|
|
|
Term
What does parasympathetic control of the heart cause? |
|
Definition
- decreased heart rate
- decreased excitability of the AV node
- shortens the action potential of atrial contractile cells
|
|
|
Term
What happens during sympathetic control of the heart? |
|
Definition
- the sympathetic nerve releases norepinephrine which binds to the beta-adrenalgic receptor coupled to stimulatory G protein which accelerates the cAMP pathway
|
|
|
Term
What does sympathetic control of the heart cause? |
|
Definition
- increased heart rate; reduces AV nodule delay
- speeds up the spread of action potential
- increases contractile strength of atrial and ventricle cells
|
|
|
Term
Where is the cardiovascular control center located? What does it control? |
|
Definition
- in the brain stem
- it controls heart rate
|
|
|
Term
|
Definition
|
|
Term
What determines stroke volume? |
|
Definition
the extent of venous return and by sympathetic activity |
|
|
Term
What is intrinsic control? |
|
Definition
the extent of venous return |
|
|
Term
What is extrinsic control? |
|
Definition
the extent of sympathetic stimulation |
|
|
Term
An increased end-diastolic volume results in increased ____________. |
|
Definition
|
|
Term
|
Definition
|
|
Term
What does blood flow through vessels depend on? |
|
Definition
pressure gradient and vascular resistance |
|
|
Term
How does pressure gradient affect blood flow? |
|
Definition
the higher the pressure gradient, the larger the blood flow |
|
|
Term
How does vascular resisstance affect blood flow? |
|
Definition
the higher the resistance, the less blood flow |
|
|
Term
Where is pressure gradient measured? |
|
Definition
|
|
Term
Where is resistance measured? |
|
Definition
|
|
Term
What three factors of the blod vessels affects resistance? |
|
Definition
- viscosity
- vessel length
- vessel diameter
|
|
|
Term
What is the main determinant of vascular resistance? |
|
Definition
|
|
Term
What is the formula for calculating blood flow? |
|
Definition
F = change in pressure/ resistance |
|
|
Term
As the difference in pressure between the two ends of the vessels increases, blood flow (increases/decreases). |
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
What are the two main functions of arteries? |
|
Definition
- to serve as a rapid transit-passage pathway for blood from the heart to tissues
- to act as a pressure reservoir to provide a driving force for blood when the heart is relaxing
|
|
|
Term
What are the two main arteries? |
|
Definition
the pulmonary artery and the aorta |
|
|
Term
What is arterial endothelial lining made up of? |
|
Definition
smooth muscle and two connective tissues, collagen and elastin |
|
|
Term
Arteries are analogous to a _______. |
|
Definition
|
|
Term
Arterioles are analogous to a ___________. |
|
Definition
|
|
Term
Capillaries are analogous to _________. |
|
Definition
|
|
Term
Veins are analogous to _________. |
|
Definition
|
|
Term
What is Professor Han's favorite movie? |
|
Definition
|
|
Term
When the heart is contracting and emptying, what happens to the arteries? |
|
Definition
|
|
Term
What happens when the heart is relaxing and filling? |
|
Definition
|
|
Term
|
Definition
|
|
Term
What causes the dicrotic notch in arterial blood pressure? |
|
Definition
when the aortic valve closes, the pressure increases slightly, causing a temporary increase in blood pressure |
|
|
Term
What is the main driving force for arterial blood flow? |
|
Definition
|
|
Term
What is the formula for mean arterial pressure? |
|
Definition
mean arterial pressure = diastolic pressure + (1/3)(systolic pressure-diastolic pressure) |
|
|
Term
If someone's blood pressure is 120/80, what is their systolic and diastolic pressure? |
|
Definition
systolic: 120
diastolic: 80 |
|
|
Term
If someone's blood pressure is 120/80, what is their mean arterial pressure? |
|
Definition
80 + (1/3)(120-80) = 93.333 |
|
|
Term
What is the function of arterioles? |
|
Definition
they control blood distribution and are the major resistance vessels |
|
|
Term
Why are arterioles considered to be the major resisatnce vessels? |
|
Definition
they create more resistance in vessels that lead to parts of the body where they don't want to send blood |
|
|
Term
What happens during vasoconstriction? |
|
Definition
there is increased contraction of circular smooth muscle in the arteriolar wall, which leads to increased resistance and decreased flow through the vessel |
|
|
Term
What happens during vasodilation? |
|
Definition
there is decreased contraction of circular smooth muscle in the arteriolar wall which leads to decreased resistance and increased flow through the vessel |
|
|
Term
What things can cause vasoconstriction? |
|
Definition
- increased myogenic activity
- increased oxygen consumption
- decreased CO2 and other metabolites
- endothelin
- sympathetic stimulation
- vasopressin, angiotensin II
- cold
|
|
|
Term
What things can cause vasodilation? |
|
Definition
- decreased myogenic activity
- decreased O2
- increased Co2 and other metabolites
- increased nitric oxide
- decreased sympathetic stimulation
- histamine release
- heat
|
|
|
Term
|
Definition
|
|
Term
What is local (intrinsic) control of arteriolar radius important for? |
|
Definition
determines the distribution of cardiac output |
|
|
Term
_________ increases blood supply to meet metabolic demands. |
|
Definition
|
|
Term
High resistance causes _____ flow. |
|
Definition
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|
Term
Moderate resistance causes _______ flow. |
|
Definition
|
|
Term
Low resistance causes ____ flow. |
|
Definition
|
|
Term
When going from rest to doing exercise, how much does the amount of blood flow to the brain change? |
|
Definition
|
|
Term
What local metabolic influences on the arteriolar radius help match blood flow with tissue needs? |
|
Definition
- decreased O2
- increased CO2
- increased acid (from increased CO2)
- increased K+ (action potential)
- increased osmolarity
- adenosine release
|
|
|
Term
What is extrinsic sympathetic control of arteriolar radius most important for? |
|
Definition
the regulation of arterial blood pressure |
|
|
Term
What are the formulas for flow and pressure difference? |
|
Definition
- flow= difference in pressure/ rate
- difference in pressure = flow x rate
|
|
|
Term
What is the main function of sympathetic stimulation in the cardiovascular system? |
|
Definition
- constricts blood vessesl to help maintain pressure
|
|
|
Term
How do norepinephrine and alpha adrenergic receptors interact? |
|
Definition
Norepinephrine combines with an alpha adrenergic receptor, inducing vasoconstriction for assuring blood supply to the brain in the expense of other organs |
|
|
Term
______ controls override sympathetic vasoconstriction and increasing blood supply. |
|
Definition
|
|
Term
There is a lack of _______________ innervation to most arterioles. |
|
Definition
|
|
Term
How many large arterial branches are there? |
|
Definition
|
|
Term
How many arterioles are there? |
|
Definition
|
|
Term
How many capillaries are there? |
|
Definition
|
|
Term
How many large veins are there? |
|
Definition
|
|
Term
How many aortas are there? |
|
Definition
|
|
Term
How many vena cavas are there? |
|
Definition
|
|
Term
What is the wall thickness of the aorta? |
|
Definition
|
|
Term
What is the wall thickness of large arterial branches? |
|
Definition
|
|
Term
What is the wall thickness of arterioles? |
|
Definition
|
|
Term
What is the wall thickness of capillaries? |
|
Definition
|
|
Term
What is the wall thickness of large veins? |
|
Definition
|
|
Term
What is the wall thickness of vena cava? |
|
Definition
1.5 mm (1,500 miscrometers) |
|
|
Term
Name all the different blood vessels from largest wall thickness to smallest wall thickness. |
|
Definition
- aorta
- vena cava
- large arterial branches
- large veins
- arterioles
- capillaries
|
|
|
Term
Name all the blood vessels in order from largest internal radius to smallest. |
|
Definition
- vena cava
- aorta
- large veins
- large arterial branches
- arterioles
- capillaries
|
|
|
Term
What is the function of the aorta and large arterial branches? |
|
Definition
passageway from the heart to the tissues; serve as a pressure reservoir |
|
|
Term
What is the function of arterioles? |
|
Definition
primary resistance vessels; determine the distribution of cardiac output |
|
|
Term
What is the function of capillaries? |
|
Definition
site of exchange; determine the distribution of extracellular fluid between the plasma and the interstitial fluid |
|
|
Term
What is the function of large veins and the vena cava? |
|
Definition
passageway of the heart to the tissues; serve as a blood reservoir |
|
|
Term
How arteries and arterioles act as pressure reservoirs? |
|
Definition
the elastic walls collapse inwards during ventricular diastole (when there is less blood in the arteries) |
|
|
Term
In humans, what is the range for blood pressure? |
|
Definition
120 mm Hg during systole and 80 mm Hg during diastole |
|
|
Term
What is the difference between systolic and diastolic pressure called? |
|
Definition
|
|
Term
Arterioles distribute ___________ among _______ whose needs vary over time. |
|
Definition
cardiac output, systemic organs |
|
|
Term
____________ varies as a result of vasodilation and vasoconstriction. |
|
Definition
resistance (and therefore blood flow) |
|
|
Term
What two factors influence the radius of arterioles? |
|
Definition
- intrinsic (local) control due to increased CO2 or decreased O2
- extrinsic control due to the autonomic nervous system
|
|
|
Term
Sympathetic ______. Parasympathetic _________. |
|
Definition
|
|
Term
|
Definition
the site of exchange for materials between blood and tissues |
|
|
Term
Exchange may occur by ___________. |
|
Definition
|
|
Term
What characteristics enhance diffusion at capillaries? |
|
Definition
- thin capillary walls
- narrow capillaries (so the red blood cells and plasma are close to the walls)
- large numbers, providing alot of surface area
- relatively slow flow of blood (providing more time for exchange to occur)
|
|
|
Term
How thick are the walls of capillaries? |
|
Definition
|
|
Term
How many capillaries do humand have? |
|
Definition
|
|
Term
What is another way that exchange may occur at capillaries? |
|
Definition
- through pores (located between the cells that form the capillary walls)
- by vesicular transport (ex: pinocytosis)
- by bulk flow
|
|
|
Term
What is the function of the water-filled pores in the capillary wall? |
|
Definition
they permit passage of small, water soluble sunstances that can cannot cross the endothelial cells themselves |
|
|
Term
What types of substances pass through the endothelial cells of capillaries? Give examples. |
|
Definition
lipid soluble substances; O2 and CO2 |
|
|
Term
Give specific examples of sunsatnces that can pass through the pores in the capillary walls. |
|
Definition
Na+, K+, glucose, amino acids |
|
|
Term
What type of substances are exchanges across the capillary walls via vesicular transport? |
|
Definition
|
|
Term
Can plasma proteins cross the capillary wall? |
|
Definition
|
|
Term
Interstitial fluid acts as an ____________ between blood and cells. |
|
Definition
|
|
Term
What happens to capillaries during resting conditions? What structure allows this? |
|
Definition
they are closed ; pre-capillary sphincters |
|
|
Term
What is the function of pre-capillary sphincters? |
|
Definition
they act as stop cocks to control blood flow through the particular capillary |
|
|
Term
When tissue metabolic activity increases, what happens? |
|
Definition
- the level of O2 decreases and the level of CO2 increases, causing relaxation of the pre-capillary sphincters and arteriolar vasodilation
|
|
|
Term
What is the function of veins? |
|
Definition
they serves as low-resistance passage-ways to return blood from the tissues to the heart |
|
|
Term
What extrinsic factors enhance venous return? |
|
Definition
- sympathetic activity
- skeletal muscle activity
- respiratory activity
- cardiac suction
|
|
|
Term
How does skeletal muscle activity enhance venous return? |
|
Definition
muscle contraction increases venous return (skeletal muscle pump) |
|
|
Term
How does respiratory activity increase venous return? |
|
Definition
the lower atmospheric pressure in the chest cavity helps to bring blood from the lower body |
|
|
Term
How does the skeletal muscle pump work? |
|
Definition
- when a skeletal muscle contracts, the upstream venous valve closes so that there is no backflow and blood is squeezed on to the next section of vein where the valve is open
|
|
|
Term
Veins serve as a ____________. |
|
Definition
|
|
Term
Under resting conditions, how much of your blood is located in the veins? Because of this, veins are important in permitting changes in __________. |
|
Definition
|
|
Term
|
Definition
the interstitial fluid that is picked up by vertebrate lymphatic vessels and returned to the venous system, meanwhile passing through the lymph nodes for venous purposes |
|
|
Term
What structures are included in the lymph system? |
|
Definition
lymph nodes, bone marrow, liver, spleen, and the thymus |
|
|
Term
What are the functions of the lymphatic system? |
|
Definition
- absorbs excess fluid, thus preventing tissues from swelling
- defends the body against microorganisms and harmful foreign particles as part of the immune system
- facilitiates the absorption of fat
|
|
|
Term
What are the factors that affect blood pressure? |
|
Definition
- peripheral resistance (vessel diameter, blood viscosity, vessel length)
- cardiac output (or heart rate combined with stroke volume)
- vessel elasticity
- blood volume
|
|
|
Term
Obesity increase vessel _______. |
|
Definition
|
|
Term
What is coronary circulation? |
|
Definition
circulation of blood in the blood vessels that supply blood to and from the heart muscle |
|
|
Term
What happens when there is reduced O2 in the cardiac myocytes? |
|
Definition
- adenosine release
- vasodilation of coronary vessels
- increased blood flow and O2 delivery to cardiac myocytes
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Term
What are the main energy sources for the heart (from oxidative phosphorylation)? |
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Definition
- fatty acids, glucose, and lactate
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Term
What is the major energy source for the heart in normal adults? |
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Definition
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Term
What is the major energy source for the heart in a fetus? |
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Definition
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