N262 CIRCULATION EXAM QUESTIONS AND ANSWERS
WITH COMPLETE SOLUTIONS GRADED A++
Circulation through the heart
Blood flow of the heart
From the superior vena cava right into the right atrium → through tricuspid valve to right
ventricle → through pulmonic valve into the pulmonary trunk and to the lungs via the
pulmonary arteries (deoxygenated)
From the lungs into the left atrium via the pulmonary veins (oxygenated → through the
bicuspid (mitral) valve into the left ventricle → through the aortic valve and then
travelling to the systemic circulation to perfuse the tissues.
Cardiac anatomy
The left side of the heart pumps oxygenated blood into the arteries.
Deoxygenated blood returns via the venous system into the right side of the heart.
Primary functions of the heart
-transporting oxygen, nutrients, and hormones to cells, and metabolic wastes from the
tissues for elimination;
-regulating body temperature, pH, and fluid volume
-preventing infection and blood loss.
Cardiac cycle
, With each heartbeat, the myocardium goes through a cycle of contraction (systole) and
relaxation (diastole)
Systole
the period when the vessels contract; when the heart ejects (propels) the blood into
pulmonary and systemic circulation.
s1 sound = beginning of systole (closure of AV valves-tricuspid and mitral)
Diastole
relaxation of the heart; when the ventricles fill with blood
s2 sound = beginning of diastole (closure of semilunar valves-aortic and pulmonic)
Cardiac Output
The amount of blood your heart is able to pump out in one minute
Stroke volume x heart rate
Stroke volume
the amount of blood pumped by the left ventricle of the heart in one contraction.
normal 4-8L/min
Factors affecting cardiac output
stroke volume heart rate, contractility, preload, afterload
Contractility
strength of the heart's contraction during systole
WITH COMPLETE SOLUTIONS GRADED A++
Circulation through the heart
Blood flow of the heart
From the superior vena cava right into the right atrium → through tricuspid valve to right
ventricle → through pulmonic valve into the pulmonary trunk and to the lungs via the
pulmonary arteries (deoxygenated)
From the lungs into the left atrium via the pulmonary veins (oxygenated → through the
bicuspid (mitral) valve into the left ventricle → through the aortic valve and then
travelling to the systemic circulation to perfuse the tissues.
Cardiac anatomy
The left side of the heart pumps oxygenated blood into the arteries.
Deoxygenated blood returns via the venous system into the right side of the heart.
Primary functions of the heart
-transporting oxygen, nutrients, and hormones to cells, and metabolic wastes from the
tissues for elimination;
-regulating body temperature, pH, and fluid volume
-preventing infection and blood loss.
Cardiac cycle
, With each heartbeat, the myocardium goes through a cycle of contraction (systole) and
relaxation (diastole)
Systole
the period when the vessels contract; when the heart ejects (propels) the blood into
pulmonary and systemic circulation.
s1 sound = beginning of systole (closure of AV valves-tricuspid and mitral)
Diastole
relaxation of the heart; when the ventricles fill with blood
s2 sound = beginning of diastole (closure of semilunar valves-aortic and pulmonic)
Cardiac Output
The amount of blood your heart is able to pump out in one minute
Stroke volume x heart rate
Stroke volume
the amount of blood pumped by the left ventricle of the heart in one contraction.
normal 4-8L/min
Factors affecting cardiac output
stroke volume heart rate, contractility, preload, afterload
Contractility
strength of the heart's contraction during systole
