Cardiovascular System Flashcards
what is the cv system comprised of?
heart and blood vessels
hearts main function?
pump oxygenated blood into systemic circulation (body organs) and deox blood into pulmonary circulation (lungs)
where does pressure drop occur?
where is bp greatest?
blood flow from arteries to veins
- greatest in arterioles
- greater in systemic compared to pulmonary circuit
where is the mitral valve?
left side, between left atrium and left ventricle
where is the aortic valve?
is it tri/bicuspid?
left side, between the left ventricle and aorta
bicuspid
where is the pulmonary valve? is it tri/bicuspid?
right side, between right ventricle and pulmonary artery
tricuspid
what does ECG stand for?
electrocardiogram
what does it record?
how is voltage detected?
the time dependent spread of electrical activity through the heart
- voltage is compared at two different points on the body surface using electrodes, not actual ap
describe the spread of cardiac impulse using pqrst wave
- impulse generated at SAN, invades atria
- atrial depolarisation generates P wave
- impulse delayed at AV node
- ventricles invaded by impulse and depolarised O QRS complex
- ventricles uniformly depolarised- ST segment
- ventricles REPOLARISE- T wave
what can R-R interval be used to measure?
HR
measure distance between the peaks of two consecutive QRS complexes at a known recording speed
HR= 1/R-R interval
what does myocardial infarction look like on an ECG?
ST elevation
what does ventricular fibrillation look like on an ECG?
rapid, irregular heart rhythm
what is the function of intercalated discs in cardiac muscle?
have GAP JUNCTIONS (electrical synapses)- provide a low resistance electrical coupling between myocardial cells
ie gap junctions (electrical synapses) make it easier for electrical coupling between cardiac cells
what is the function of intercalated discs in cardiac muscle?
have GAP JUNCTIONS (electrical synapses)- provide a low resistance electrical coupling between myocardial cells
ie gap junctions (electrical synapses) make it easier for electrical coupling between cardiac cells
why are gap junctions in cardiac muscle important?
- allow efficient propagation of action potential O coordinated muscle contraction of muscle cells
