Heart Structure Flashcards
(17 cards)
Overall structure
4 chambers
2 atria
2 ventricles
Semi lunar valves
Atrioventricular valves
4 main blood vessels
Aorta
Vena cava
Pulmonary vein
Pulmonary artery
Myogenic meaning
Beats and itself
Coronary arteries
Arteries around the outside of the heart
Valves
Semi lunar between ventricles and arteries
Biscuspid (left) and tricuspid (right) atrioventricular valves are between atria and ventricles
Cardiac cycle
1) diastole- relaxation: blood sources AV valves open and semi lunar valves close- pressure lower in ventricles than arteries
2) atrial systole: SAN transmits impulses to atria- contracts and blood forced into ventricle
3) ventricular systole: impulses pass to AVN from atria- impulses pass to bundle of his then to small muscle fibres- ventricle contracts bottom up and force blood up arteries
Why is there a short delay between the electrical wave entering AVN and leavibg
Non conductive tissue in septum
Lets atria empty before ventricle contracts
Role of SAN
Sends electrical impulses
Initiates heartbeat
Acts as pacemaker
Location of SAN
Right atrium
Sound of heartbeat caused by …
Valves opening and closing
Which chamber contracts more powerfully
Ventricles and the left side
(Left ventricle)
When do semi lunar valves open
When ventricle volume is highest and decreasing
Renal meaning
Kidney blood vessels
Pulmonary
Lung blood vessels
Cardiac output equation
Cardiac output = heart rate x stroke volume
When do atrioventricular valves close
When ventricles contract and pressure of ventricles is higher than pressure in atria
Blood movement in relationship to pressure
Moves down pressure gradient
