Intro to Cardiovascular System Flashcards
Cardiovascular system
A closed system of the heart and blood vessels
the heart pumps
blood
blood vessels allow blood to…
circulate to all parts of the body
function
to deliver oxygen and nutrients and to remove carbon dioxide and other waste products
location of heart/characteristics
-thorax between the lungs (mediastinum)
-pointed apex directed toward left hip
-about the size of your fist
-less than 1 lb
Pericardium
a double serous membrane
Visercal pericardium
next to heart
Parietal pericardium
outside layer
Serous fluid
fills the space between the layers of pericardium
how many layers is the heart wall
3: epi, myo, endo
Epicardium
-outside layer
-parietal pericardium
-connective tissue layer
Myocardium
-middle layer
-mostly cardiac muscle
Endocardium
-inner layer
-endothelium
how many chambers
4: atria, ventricles
right and left side act as separate pumps
Atria
-receiving chambers (right and left)
Ventricles
-discharging chambers (right and left )
Valves
-4
-allow blood to flow in only one direction
Atrioventricular valves
between atria and ventricles
-bicuspid (left), tricuspid (right)
Semilunar
valves between ventricle and artery
-pulmonary, aortic
valves
-valves open as blood is pumped through
-held in place by chordae tendineae (heart strings)
-close to prevent backflow
Valves pathology
-incompetent valve= backflow and repump
-stenosis= stiff= heart workload increased
Lup
bicuspid and mitral valve or AV valves close
Dub
aortic and pulmonary or semilunar valves close
aorta
leaves left ventricle
pulmonary arteries
leave right ventricles
vena cava
enters right atrium
pulmonary veins
-4; enter left atrium
blood in the heart chambers does not…
nourish the myocardium
the heart has its own nourishing circulatory system
-coronary arteries
-cardiac veins
blood empties into the right atrium via the
coronary sinus
