1.4 Function of the heart Flashcards
How does the heart act as a double pump?
Sends de-oxygenated blood to the lungs whilst simultaneously sending oxygenated blood coming from the lungs to the rest of the body.
When the atria contracts, where does it push the blood and through what valves?
Pushes blood down into the ventricles through the tricuspid valve (right) and the bicuspid valve (left).
Once the ventricles are full, where do they squeeze the blood?
Upwards.
Once the blood is pushes upwards, what happens to the tricuspid and bicuspid valves?
They are forced to simultaneously close, creating a ‘lub’ sound.
After the valves are forced shut, where is the blood forced out of?
Forced out of the pulmonary artery and aorta.
Once the blood is forced out of the pulmonary valve and aorta, what happens to the semi-lunar valves?
They simultaneously snap shut.
Why do the semi-lunar valves snap shut?
To prevent backflow.
What are contractions of the heart known as?
Systole.
What is relaxation of the heart known as?
Diastole.
What is atrial systole?
Contraction of the atria.
What is ventricular systole?
Contraction of the ventricles.
What is cardiac diastole?
Relaxation of the atria and ventricles.
When the heart is in diastole, is the atrioventricular valve open or closed?
Open.
When the heart is in diastole, is the semilunar valve open or closed?
Closed.
When the heart is in systole, is the atrioventricular valve open or closed?
Closed.
