The Cardiac Cycle Flashcards
What does the cardiac cycle display?
The cardiac cycle displays the volume and pressure changes within the heart and how they control the open and closing of the valves
What is the function of the valves?
The valves control blood flow towards one direction
What stages does the cardiac cycle split itself into?
The cardiac cycle splits itself into the diastole stage, atrial systole stage and the ventricular systole stage
What does the term ‘diastole’ refer to?
Relaxing. So if the atriums/ventricles are in diastole, they are relaxing
What does the term ‘systole’ refer to
Contracting. So if the atriums/ventricles are in systole they are contracting
What occurs in the diastole stage? Explain what happens in the body
In the diastole stage, both the atrial and ventricular muscles become relaxed.
This is when blood enters the atrium through the vena cava and pulmonary vein due to the increased volume.
This increased volume causes an increase in pressure inside the aorta
What occurs in the atrial systole stage? Explain what happens in the body
The atrium’s muscular walls contract, decreasing the volume within the atria and further increases the pressure
This leads to the atrioventricular valves to open and have blood flow into the ventricles. The ventricular muscular walls remain relaxed
What occurs in the ventricular diastole stage? Explain what happens in the body
The ventricle’s muscular walls contract, decreasing the volume and increasing the pressure beyond the atria.
This shift in pressure and volume causes the atrioventricular valves to close and the semi-lunar valves to open
When the ventricular muscular walls contract, the blood is pushed out of the ventricles into the arteries
When the muscular walls contract what does it mean in scientific language?
The muscular walls contracting refers to the walls going into systole
When the muscular walls relax, what does it mean in scientific language?
The muscular walls relaxing is when they go into diastole
What does the cardiac output measure?
The cardiac output measure the volume of blood which leaves one ventricles in one minute
What is the formula for the cardiac output?
CARDIAC OUTPUT = heart rate x stroke volume
What does the heart rate represent in the equation? What does the stroke volume represent in the equation?
The beats of the heart per minute (min^-1)
The volume of blood that leaves the heart each beat (dm^3)
Where are the semi lunar valves located?
In the aorta and pulmonary artery
Where are the atrioventricular valves located?
Between the atria and ventricles
