B4M2Q2 24-25 Flashcards
Gas and nutrient exchange occurs in only one component of the circulatory
system. Which of the following allows such exchange?
A. Pump (heart)
B. Lymphatic system
C. Conduits (blood vessels)
D. Capillary-Endothelial System
D. Capillary-Endothelial System
When a patient bleeds, from which part of the circulatory system does the
immediate infusion of volume to increase the circulating volume come from?
A. Heart and Lungs
B. Venules & systemic veins
C. Aorta, arteries and arterioles
D. Pulmonary vessels & capillaries
B. Venules & systemic veins
In the earliest phases of septic shock, BP may still be normal despite signs of
hypoperfusion. Which of the following explains this?
A. BP is maintained by increasing SVR that compromises perfusion
B. The cardiac output is inversely related to the Blood Pressure
C. The stroke volume (SV) is augmented by tachycardia
D. Hydrostatic pressure increases during shock stat
A. BP is maintained by increasing SVR that compromises perfusion
A 55-year old lineman was electrocuted, suffered 3rd degree burns over 60% of
his body with massive loss of protein-rich exudation. He is admitted with BP 90/50. Which of the following processes will ensue?
A. The heart rate will increase
B. The interstitial space will contract
C. Angiotensinogen production is suppressed
D. The GI tract becomes hyperactive due to hypoperfusi
A. The heart rate will increase
How do you interpret the formula: Flow (Q) = Pressure gradient/Resistance
A. The greater the resistance, the more the flow
B. Flow increases as the pressure gradient decreases
C. Decrease in resistance will increase the blood flow
D. Pressure gradient is inversely related to the degree of resistance
C. Decrease in resistance will increase the blood flow
The human body is composed of 60 - 75% water. In which of the following is the
majority of this water located?
A. Intravascular space
B. Intracellular space
C. Lymphatic space
D. Interstitial spac
B. Intracellular space
After the release of a medical tourniquet, the patient reported that his heart was pounding in his chest. Vital signs were otherwise normal. Which principle explains this?
A. Ohm’s Law
B. Bohr’s law of fluids
C. Starling’s law of the heart
D. Pousseille’s law of blood flo
C. Starling’s law of the heart
With a normal cardiac structure and function, the total amount of blood at any
given time is:
A. Greatest in the systemic circulation
B. The same in all parts of the circulatory system
C. Always greatest in the tissue with the fastest metabolism
D. Regulated according to the dictates of the neuro-endocrine system
B. The same in all parts of the circulatory system
Which of the following is TRUE of the cardiac cycle?
A. The atria provide the major source of power for moving blood through the
body’s vascular system
B. The ventricles contract ahead of atrial contraction.
C. Each cycle is initiated by spontaneous generation of action potential in the sinus node.
D. Increasing heart rate increases the duration of each cycle.
C. Each cycle is initiated by spontaneous generation of action potential in the sinus node.
Which of the following happens during isovolumetric contraction?
a. The second heart sound is produced at this time.
b. There is ventricular contraction but no emptying occurs.
c. It begins right before onset of QRS wave.
d. Ventricular pressure gradually rises.
b. There is ventricular contraction but no emptying occurs.
Which of the following occurs during rapid ventricular ejection?
a. There is maximum increase in ventricular pressure.
b. Opening of the aortic valve is caused by high aortic pressure.
c. The onset of T wave marks the beginning of the contraction.
d. Ventricular volume is unchanged
a. There is maximum increase in ventricular pressure.
What happens during the isovolumetric contraction of the ventricles?
a. It begins at the period of when blood starts to fill the ventricles.
b. The ventricles are half filled at 120ml.
c. With excitation, the ventricles contract but maintain its pressure.
d. When all valves are closed, no more blood can be ejected from the ventricle.
d. When all valves are closed, no more blood can be ejected from the ventricle.
Which of the following characteristic waves is the record of jugular pressure that
represents atrial systole?
a. a wave
b. b wave
c. c wave
d. v wave
a. a wave
Which of the following features tell us about atrial systole of the cardiac cycle?
a. Repolarization of the ventricle is complete
b. Atrial systole is preceded by the p wave
c. Ventricular filling continues but at a slower rate
d. Atrial systole causes the second heart soun
b. Atrial systole is preceded by the p wave
Which pressure in the left ventricle can push the semilunar valves open?
a. >60mmHg
b. >70mmHg
c. >80mmHg
d. >90mmHg
c. >80mmHg
In which of the following areas is the second heart sound (S2) loudest?
A. Cardiac apex
B. Precordium
C. Lower left sternal border
D. Base of the heart
D. Base of the heart
Which of the following best describes S3?
A. It occurs during rapid ventricular filling phase of diastole
B. It is associated with premature closure of the aortic and pulmonic valves
C. It is a high- pitched sound that precedes S2
D. It is a low pitched sound heard one-third through systo
A. It occurs during rapid ventricular filling phase of diastole
Which component of S2 occurs first and why?
A. P2 because it occurs immediately after the closure of the mitral valve
B. A2 because the left ventricle finishes systole first
C. P2 because of higher compliance in the pulmonary circulation
D. A2 because of the higher pressures in the aorta
D. A2 because of the higher pressures in the aorta
A patient with heart failure presents with an S3 and S4 sound. Which of the
following could be a recommended treatment plan for improving heart function?
A. Diuretic therapy to reduce preload
B. Calcium channel blockers to relax the ventricles
C. Increased fluid intake to reduce heart strain
D. Beta- blockers to slow heart rate and reduce systolic pressure
A. Diuretic therapy to reduce preload
Which receptor is primarily involved in the inotropic effect of catecholamines on
the heart?
A. Alpha-1 adrenergic receptor
B. Beta-1 adrenergic receptor
C. Muscarinic receptor
D. Nicotinic receptor
B. Beta-1 adrenergic receptor
How does the action of cardiac glycosides affect the calcium cycle in myocardial
cells?
A. By increasing the sodium gradient across the membrane, promoting
calcium extrusion.
B. By inhibiting the sodium-potassium ATPase, leading to higher intracellular calcium
C. By increasing the activity of the calcium pump in the sarcoplasmic reticulum
D. By decreasing the rate of calcium influx during action potentials
B. By inhibiting the sodium-potassium ATPase, leading to higher intracellular calcium
Which of the following is the average cardiac output of a resting, supine man?
A. 3.5 L/min
B. 5.0 L/min
C. 6.5 L/min
D. 7.5 L/min
B. 5.0 L/min
Which of the following is the term for the amount of blood pumped out of each
ventricle per beat?
A. End-diastolic volume
B. Stroke volume
C. Ejection fraction
D. Cardiac index
B. Stroke volume
Which is the approximate ejection fraction of the heart in a healthy individual?
A. 40%
B. 50%
C. 60%
D. 70%
C. 60%
Which factor primarily controls the heart rate?
A. Blood pressure
B. Autonomic Nervous System
C. Oxygen levels
D. Stroke volume
B. Autonomic Nervous System
Which action occurs during the isovolumetric contraction phase of the ventricular
pressure-volume loop?
A. Blood is ejected from the ventricle
B. The ventricular muscle is relaxed
C. Ventricular pressure increases while the volume remains constant
D. The mitral valve opens for ventricular filling
C. Ventricular pressure increases while the volume remains constant
In the Frank-Starling mechanism, which of the following happens as the end-
diastolic volume increases?
A. The heart rate decreases
B. The force of contraction decreases
C. The stroke volume increases
D. The afterload increases
C. The stroke volume increases
Which of the following components of the vascular system have the largest total
cross-sectional and surface area?
A. Arteries
B. Capillaries
C. Veins
D. Arterioles
B. Capillaries
Among the components of the vascular system, which pf the following exhibit the
highest resistance?
A. Arteries
B. Capillaries
C. Veins
D. Arterioles
D. Arterioles
Which of the following are expected to contain the highest proportion of blood in
the cardiovascular system?
A. Arteries
B. Capillaries
C. Veins
D. Arterioles
C. Veins
The diameter of arterioles is said to be less than:
A. 0.1 cm
B. 0.1 mm
C. 0.5 cm
D. 0.5 mm
B. 0.1 mm
Which of the following is TRUE of the site of exchange of nutrients, water and
gases?
A. They have the largest total cross-sectional and surface area.
B. They exhibit the highest resistance in the cardiovascular system.
C. They contain the highest proportion of blood in the vascular system.
D. They are thick-walled and exhibit high pressure
A. They have the largest total cross-sectional and surface area.
Which is the innermost layer of blood vessels?
a. Tunica intima
b. Tunica media
c. Tunica externa
d. Endothelium
a. Tunica intima
Which layer of blood vessels is responsible for regulating blood flow and
pressure?
a. Tunica intima
b. Tunica media
c. Tunica externa
d. Endothelium
b. Tunica media
Which type of blood vessel has the thickest tunica externa?
a. Artery
b. Vein
c. Capillary
d. Venule
b. Vein
Which blood vessel type has valves to prevent the backflow of blood?
a. Artery
b. Vein
c. Capillary
d. Venule
b. Vein
Which is the function of smooth muscle in the tunica media of blood vessels?
a. Nutrient exchange
b. Regulation of blood flow and pressure
c. Oxygen transport
d. Waste removal
b. Regulation of blood flow and pressure
Which blood vessel type has the thinnest walls and is responsible for nutrient and
gas exchange?
a. Artery
b. Vein
c. Capillary
d. Venule
c. Capillary
A patient presents with symptoms of hypertension. Which histologic feature of
blood vessels is most likely to be affected in this condition?
a. Thick tunica intima
b. Thin tunica media
c. Weak tunica externa
d. Disrupted endothelium
d. Disrupted endothelium
How is capacitance defined in the context of blood vessels?
A. The ability of a blood vessel to contract and relax in response to changes in pressure
B. The ability of a blood vessel to store and release blood in response to changes in pressure
C. The ability of blood vessels to regulate blood flow through vasoconstriction and vasodilation
D. The maximum amount of blood a blood vessel can carry at any given time
B. The ability of a blood vessel to store and release blood in response to changes in pressure
Which type of blood vessel has the highest capacitance?
A. Arteries
B. Arterioles
C. Capillaries
D. Veins
D. Veins
Which of the following explains why the blood flow velocity is lowest in the
capillaries?
A. Capillaries are designed to slow down blood for nutrient exchange
B. Capillaries have the smallest diameter, which reduces flow velocity
C. Blood is diverted to capillaries from larger vessel, causing slower movement
D. Capillaries have higher resistance compared to arteries
A. Capillaries are designed to slow down blood for nutrient exchange
Considering the formula for blood flow velocity, what happens to the blood flow
velocity as blood moves from large arteries to the capillaries?
A. It increases
B. It remains constant
C. It decreases
D. It is fluctuating
C. It decreases
Cardiac output (CO) is commonly expressed as:
A. CO = stroke volume x heart rate
B. CO = mean arterial pressure x total peripheral resistance
C. CO = hear rate x blood pressure
D. CO = stroke volume + heart rate
A. CO = stroke volume x heart rate
Which of the following explains why the greatest pressure decrease in the circulation occurs across the arterioles?
A. They have the greatest surface area
B. The have the greatest cross-sectional area
C. The velocity of blood flow through them is the lowest
D. They have the greatest resistance
D. They have the greatest resistance
During exercise, blood flow distribution changes to
meet the body’s increased
metabolic demands. Which of the following correctly describes the relative
changes in blood flow to various organs during moderate to intense exercise?
A. Increased blood flow to skeletal muscles and skin; decreased blood flow
to the heart, brain, and abdominal viscera.
B. Increased blood flow to the heart, skeletal muscles, and skin; decreased blood flow to the abdominal viscera; no significant change in brain blood flow.
C. Decreased blood flow to skeletal muscles and the brain; increased blood
flow to the heart, skin, and abdominal viscera.
D. No significant change in blood flow to any organs; total cardiac output
remains constant
B. Increased blood flow to the heart, skeletal muscles, and skin; decreased blood flow to the abdominal viscera; no significant change in brain blood flow.
During a marathon, a runner experiences increased blood flow to her leg muscles. This is primarily due to:
A. Increased sympathetic vasoconstriction
B. Accumulation of metabolic byproducts such as carbon dioxide, adenosine and hydrogen ions
C. Myogenic constriction of blood vessels
D. Reduced cardiac outpu
B. Accumulation of metabolic byproducts such as carbon dioxide, adenosine and hydrogen ions
Which of the following best describes the neural mechanism of blood flow
regulation?
A. Local metabolic byproducts cause vasodilation.
B. Sympathetic nervous system activation induces vasoconstriction in most organs.
C. Endothelial cells release nitric oxide to regulate vessel diameter.
D. Myogenic responses adjust vessel diameter based on blood pressure
changes.
B. Sympathetic nervous system activation induces vasoconstriction in most organs.
A 45-year-old man suddenly stands up after sitting for an extended period. He
briefly feels dizzy before regaining stability. His body compensates for the drop in
blood pressure by activating which mechanism?
A. Increased parasympathetic stimulation causing vasodilation
B. Sympathetic activation causing vasoconstriction in the lower body
C. Myogenic vasodilation in the cerebral arteries
D. Increased nitric oxide release causing widespread vasodilat
B. Sympathetic activation causing vasoconstriction in the lower body
During exercise, which metabolic factor plays a major role in increasing blood
flow to skeletal muscles?
A. Increased oxygen levels
B. Decreased carbon dioxide levels
C. Increased adenosine and hydrogen ions
D. Increased sympathetic vasoconstriction
C. Increased adenosine and hydrogen ions
