Heart/Blood Flashcards
Generated from Lectures 18-23
The organ of propulsion in the circulatory system is the _______.
heart
The blood vessels responsible for the distribution of blood are the _______.
arteries
_______ serve as a pressure reservoir in the circulatory system.
Arteries
The transfer of materials between blood and tissues/cells occurs in the _______.
capillaries
_______ are responsible for returning blood to the heart.
Veins
Besides returning blood to the heart, the _______ also serve as a volume reservoir.
veins
The _______ side of the heart is associated with the respiratory system.
right
The _______ side of the heart is associated with the systemic circulation.
left
The _______ fluid adheres to the heart and reduces friction
pericardial
The smooth _______ minimizes surface friction in the heart.
endothelium
_______ prevents overstretching of the heart.
Fibrous pericardium
Inflammation of the pericardium is called _______.
pericarditis
The _______ valve is located between the left atrium and left ventricle.
mitral
The _______ valve is also known as the bicuspid valve.
mitral
Prolapse of the _______ valve can occur if there is too much blood volume.
mitral
The _______ valves open and close due to differential hydrostatic pressures
heart
The _______ ventricle has a thicker myocardial wall than the other ventricle.
left
The _______ valve is located between the right atrium and the right ventricle.
tricuspid
Cardiac muscle is also known as _______.
myocardium
The _______ node and atrioventricular node contain smaller myocardial fibers that are weakly contractile.
sinus
The liquid portion of blood is called _____.
plasma
Red blood cells contain the protein _____, which carries oxygen.
hemoglobin
The hormone _____ stimulates red blood cell production.
erythropoietin
Platelets release _____, which promotes blood vessel constriction.
thromboxane A2 (TXA2)
The protein _____ forms the meshwork of a blood clot.
fibrin
The _____ pathway of blood clotting is initiated by damage to the blood vessel wall.
extrinsic
Hemophilia is usually caused by a deficiency in clotting factor _____.
VIII
_____ is a medical condition characterized by a low red blood cell count.
Anemia
The _____ valve closing produces the “lub” sound of the heartbeat.
AV
The volume of blood in the ventricle at the end of diastole is called the _____.
end-diastolic volume (EDV)
The _____ is the volume of blood ejected from the left ventricle with each heartbeat.
stroke volume
How do you calculate stroke volume?
SV = EDV - ESV
_____ is the amount of blood pumped by the heart per minute.
Cardiac output
How is cardiac output calculated?
CO = HR x SV; cardiac volume = heart rate x stroke volume
An increase in _____ refers to an increase in the force of contraction of the heart muscle.
contractility
An increase in contractility in the heart leads to a _______ stroke volume for a given preload.
greater
__________ is the end-diastolic ventricular pressure, which is related to the filling and stretching of the ventricle, ultimately influencing the resting length of the cardiac muscle.
Ventricular preload
__________ refers to the systemic arterial pressure that the ventricle must overcome to open the aortic valve and eject blood.
Ventricular afterload
An increase in preload leads to an increase in _____.
stroke volume
An increase in afterload leads to a _____ in stroke volume.
decrease
The _____ wave of the ECG represents atrial depolarization.
P
The _____ complex corresponds to ventricular depolarization.
QRS
The _____ interval reflects the time it takes for the electrical impulse to travel from the atria to the ventricles.
PR
The _____ wave represents ventricular repolarization.
T
The _____ segment on the ECG should be flat and represents the period when the ventricles are contracting and the heart is ejecting blood.
ST
The _____ is the muscular layer of the heart responsible for its pumping action.
myocardium
The _____ valve is located between the left atrium and left ventricle, preventing backflow of blood.
mitral
The heart is enveloped by a protective sac called the _____, which reduces friction during heartbeats.
pericardium
The equation _____ describes the relationship between flow, pressure, and resistance in blood vessels, illustrating a fundamental concept in hemodynamics.
F = ΔP/R; Blood flow (F) is directly proportional to the pressure difference (ΔP) and inversely proportional to vascular resistance (R)
_____ are the blood vessels with the largest total cross-sectional area and the lowest flow velocity.
Capillaries
According to Poiseuille’s Law, blood vessel resistance is inversely proportional to _____ to the fourth power.
inner radius
An increase in _____ refers to an increase in the volume of blood returned to the heart via the venous system.
venous return
The _____ pressure is typically very low, close to 0 mm Hg.
venous
The _____ are the blood vessels primarily responsible for regulating resistance to blood flow.
arterioles
_____ is the relationship between the change in volume and the change in pressure within a blood vessel, reflecting the vessel’s ability to stretch and accommodate changes in blood volume.
Compliance
The equation to calculate compliance is ________.
Compliance = ΔV / ΔP
True or False: Arteries, with their thicker, more elastic walls, have lower compliance, while veins are more compliant due to their thinner walls and larger lumen.
True
___________ act as muscular valves, controlling blood flow into individual capillaries.
Precapillary sphincters
The _____ represents the average pressure exerted by blood against the walls of arteries during one cardiac cycle.
Mean Arterial Pressure (MAP)
The equation for calculating MAP is _________
MAP: MAP = DP + 1/3 (SP-DP); [DP = diastolic pressure, SP = systolic pressure}
The difference between systolic and diastolic blood pressure is known as the _____.
pulse pressure
The equation ___________, known as Poiseuille’s Law, mathematically describes the factors influencing resistance to blood flow in a blood vessel.
R = 8Lh / pr^4; Resistance = 8 (length)x(fluid viscosity) / (constant)x(inner radius)^4
The force that drives fluid movement across capillary walls is called _____.
net filtration pressure (NFP)
_____ are specialized structures in veins that prevent backflow of blood, ensuring unidirectional flow towards the heart.
Valves
An increase in _____ activity leads to vasodilation, increasing blood flow to tissues.
sympathetic
_____ is a measure of the total resistance encountered by blood flow in the systemic circulation.
Total peripheral resistance (TPR)
According to the _____ law, an increase in the volume of blood returning to the heart (venous return) leads to an increase in stroke volume.
Frank-Starling
_____ are sensory receptors located in the walls of arteries that monitor blood pressure.
Baroreceptors
_____ is the term for an abnormally elevated heart rate.
Tachycardia
_____ is the process of increasing the diameter of blood vessels, leading to decreased resistance and increased blood flow.
Vasodilation
_____ is the process of decreasing the diameter of blood vessels, leading to increased resistance and decreased blood flow.
Vasoconstriction
The _____ nervous system is responsible for increasing heart rate and contractility, preparing the body for “fight or flight” responses.
sympathetic
The _____ nervous system is responsible for decreasing heart rate, promoting rest and digestion.
parasympathetic
The percentage of red blood cells in a given volume of blood is known as the _____.
hematocrit
_____ are cell fragments in the blood that play a critical role in hemostasis by forming a plug at the site of vascular injury.
Platelets
The _____ nervous system acts to increase heart rate by increasing the inward sodium current (If) and increasing the inward calcium current (Ica).
sympathetic
A(n) _____ agent increases the strength of heart contractions at any given preload.
positive inotropic
Long-term regulation of blood pressure primarily involves adjustments in _____.
blood volume
_____ shock is a life-threatening condition that occurs due to severe blood loss, leading to a decrease in blood pressure and inadequate oxygen delivery to tissues.
Hypovolemic
The _____ is a pressure wave observed in the aortic pressure tracing during early diastole, caused by the rebound of blood against the closed aortic valve.
dicrotic notch
The second heart sound, often described as a “dub” sound, is associated with the closure of the _____ valves.
aortic and pulmonary
______ refers to the increase in ventricular volume during diastole due to the continued inflow of blood from the atria.
Ventricular filling
_______ channels play a critical role in the plateau phase of a ventricular action potential, contributing to the prolonged refractory period observed in cardiac muscle.
L-type calcium (Ca2+)
The _______ node is the primary pacemaker of the heart, initiating the electrical impulses that regulate the heartbeat.
SA
The heart controls both the __________ circulation and the __________ circulation.
systemic, pulmonary
True or False: There are different average pressures in the pulmonary and systemic circulations.
True
The distribution of blood volume is _____% in the heart, _____% in the pulmonary circulation, and ______% in the systemic circulation.
15% heart, 12% pulmonary, 73% systemic
The distribution of blood volume in the systemic circulation is _____% in the arteries, ______% in the veins, and ______% in the capillaries.
16-18% arteries, 50% veins, 5-7% capillaries
The fibrous division between the left and right ventricle is called the __________.
interventricular septum
