cardiovascular system part 1 Flashcards
function of the cardiovascular system?
transport
shape of heart
adult fist size and weighs less than a pound
- pointed apex directed toward the left hip and rests on the diaphragm.
- level of the fifth intercostals space
where is the heart located?
in the bony thorax and is flanked on each side by the lungs
heart rate also known as
apical pulse
base of heart
points towards the right shoulder and lies beneath the second rib
what is the visceral pericardium or epicardium?
thin and tightly hugs the external surface of the heart
what is the pericardium?
encloses the heart
double sac of SEROUS membrance
what is serous fluid
- slippery lubricating fluid
- produced by the serous pericardial membranes
- allows the heart to beat easily in a relatively frictionless environment as the pericardial layers slide smoothly across each other
what is pericarditis?
inflammation of the pericardium
- results in a decrease in the amount of serous fluid
- causes the pericardial layers to bind and stick to each other
- painful adhesions that interfere with heart movements
what does the myocardium consist of?
thick bundles of cardiac muscle twisted and whorled into ringlike arrangements
-it is this layer that actually contracts
what is the endocardium?
- a thin glistening sheet of endothelium that lines the heart chambers
- it is continuous with the linings of the blood vessels leaving and entering the heart
what is the interatrial septum?
the septum that divides the heart longitudinally
pulmonary circulation
right side of heart to lungs to left side
systematic circulation
left side to body tissues, to right side
which ventricle wall is thicker?
right ventricle
what do the valves do?
allow blood to flow in only one direction through the heart chambers
what the chordae tendineae
tiny white chords which (heart strings) anchor the cusps to the walls of the ventricles
the av valves are open during heart
relaxation and closed when the ventricles are contracting
blood contained in the heart does not nourish the myocardium
true
the blood supply that oxygenates and nourishes the heart is provided by …
right + left coronary arteries
coronary sinus
the myocardium is drained here by several cardiac veins
- on the backside of the heart
- empties into the right atrium
