The heart Flashcards
What is the function of the coronary arteries?
supply the caridac muscle with oxygenated blood it needs to keep contracting and relaxing all the time
What is the function of the inelastic pericardial membranes?
prevent the heart from over-distending with blood
What is the difference between the left and right side of the heart?
deoxygenated blood from the body flows into the right side of the heart, which pumps it to the lungs
oxygenated blood from the lung and returns to the left side of the heart and is pumped to the body
the left side of the heart has thicker muscle
What vessels are in the right and left side of the heart?
right
veins - superior/inferior vena cava
arteries - pulmonary arteries
left:
pulmoanry vein
aorta
What are the valves in the heart?
atrioventricular - mitral (left) and triscupid (right) valves control blood flow from the atria to the ventricles
semilunar - the aortic and pulmonary valve control blood flow out of the ventricles
How does blood get from the vena cava to the ventricles?
superior vena cava - upper body and head
blood flows in the the atria until the tricuspid valves open
when both the atrium and ventricle are filled with blood, the atrium contracts, forcing all the blood into the ventricle, which stretches its walls
How does blood get from the right ventricle to the pulmonary artery?
as the right ventricle starts to contract, the tricupsid valve close, preventing any backflow of blood to the atrium
the tendinous cords make sure the valves arent turned inside out by the pressures exerted when the ventricles contract
the right ventricle contracts and pumps deoxygenated blood through the semilunar valves into the pulmonary artery
Why are the walls thicker on the left side?
the lungs are close to the hear and are small than the rest of the body
the left side has to produce sufficient force to overcome the reistance of the aorta and arterial systems of the whole body and move blood to all extremities
