cardiovascular system Flashcards
what side of the heart is oxygenated
left
what 3 layers of tissue does the heart consist of
epicardium, myocardium, endocardium
what is the epicardium
the outer layer of connective tissue
what is the myocardium
the cardiac muscle, the bulk of the tissues in the heart
what is the role of the myocardium in the heart
connected to others by intercalated discs, which allows transmission of electrical impulses
what is the endocardium
thin layer of connective tissue, inner most tissue
what is the pericardium
the outer most tissue
what are the 2 circulatory systems and their role
systemic circulation - takes oxygenated blood around the body
pulmonary circulation - carries blood to the lungs for oxygenation and removal of carbon dioxide
which ventricle has thicker walls and why?
the left - it has to pump blood all around the body
what is the role of valves within the heart
to ensure uni-directional flow
what is the name of the two atrioventricular valves
the tricuspid and bicuspid
what noise do the atrio ventricular valves make as they close
lub
what noise do the semi-lunar valves make as they close
dub
what is the name of the two semilunar valves
aortic and pulmonary
what node begins electrical conduction in the heart
sinoatrial node
where does the depolarisation from the SAN get sent to
it causes the atrium to contract forcing blood into the ventricle due to a change in pressure between the atrium and the ventricles
what is the role of the AVN
creates a pause before sending the depolarisation to the ventricle
why does the signal travel from the apex up
to push the blood out of the ventricles as the openings are near the top
what is the system of electrical conduction
starting at the SAN
SAN - AVN - Bundle of his - bundle branches - apex - purkinje fibers
what is the role of purkinje fibres
to evenly distribute impulses through the myocardium
why are multiple leads placed during an ECG
to produce different perspective on the depolarisation of the heart
what wave is produced from the depolarisation of the atrium
P wave
the flat line after the p wave is caused by what
atrial systole ( atrial contraction)
what produces the QRS complex
the depolarisation of ventricular contractile fibres
what is the flat line after the QRS complex caused by
ventricular systole ( ventricular contraction)
what is the T wave caused by
repolarisation of ventricular contractile fibres