Heart Structure + Cardiac Cycle Flashcards
Which side of the heart is larger?
Left
Which vessel brings oxygenated blood from the lungs to the heart?
Pulmonary vein
Which vessel brings deoxygenated blood from the heart to the lungs?
Pulmonary artery
Which vessel bring deoxygenated blood from the heart to the body?
Aorta
Which vessel brings oxygenated blood from the body to the heart?
Vena cava
What is the role of the right atrioventricular valve?
Stops backflow between the right atrium and ventricle.
What is the role of the left atrioventricular valve?
Stops backflow between the left atrium and ventricle
What is the role of the septum?
Separates two sides of the heart.
What is the role of the right semi-lunar valve?
Stops backflow between the right ventricle and pulmonary artery.
What is the role of the left semi-lunar valve?
Stops backflow between the aorta and left ventricle.
How are valves opened?
By changes in pressure.
How does blood moves through the left side of the heart?
-Blood enters the left atrium via the pulmonary artery.
-Moves from the left atrium to the left ventricle as pressure increases so the left AV valve opens as the atrium contracts.
-Pressure in the left ventricle will then increase.
-Blood moves to the aorta as the SL valve opens and the ventricle contracts.
What happens in diastole?
-Blood returns to the atrium through the pulmonary vein and vena cava.
-An increase in pressure causes the AV valve to open.
-Pressure is higher in aorta aorta and pulmonary artery than ventricles so SL valve closes.
What happens in atrial systole?
-Atrium walls contract.
-Pushes remaining blood into ventricles.
-Ventricles remain relaxed and recoil.
What happens in ventricular systole?
-Atrium relaxes after a short delay where the ventricles fill with blood to ensure the ventricles contact and valves have time to close (no backflow).
-Pressure increases in ventricles which is higher than aorta and pulmonary artery so SL valve opens.
-Blood is pushed away from the heart through the PA and aorta.
