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Cardiovascular + Respiratory systems - Coggle Diagram
Cardiovascular + Respiratory systems
Overview
Function:
transports oxygen, nutrients and hormones, removes waste products
Components:
heart (cardiac muscle), blood vessels, + blood
Circuits:
pulmonary circuit - carries deoxygenated blood from heart -> lungs and oxygenated blood back
systemic circuit - carries oxygenated blood from heart -> body + deoxygenated blood back
Structure of the heart
Double pump: beats - 100,000 rimes/day
Size: about size of fist
Location: behind sternum + ribs
Divided by septum:
right side - pumps deoxygenated blood to lungs
left side - pumps oxygenated blood to body
Valves:
AV (atrioventricular) - between atria + ventricles
right tricuspid value
left bicuspid valve
SL (semi-lunar) valves - between ventricles + blood vessels
pulmonary + aortic valves
Path of blood through the heart
Left Side (oxygenated blood)
Blood from lungs enters left atrium via pulmonary vein
Blood flows through bicuspid valve into left ventricle
Blood is pumped out through aortic valve into aorta to the body
Right side (deoxygenated blood)
Blood from body enter right atrium via vena cava
Blood flows through tricuspid valve into right ventricle
Blood is pumped through pulmonary valve into pulmonary artery to the lungs
Conduction system of the heart
Heart is myogenic (produces its own electrical impulses)
Conduction Pathway
SA node (Sino-atrial node) - initiates heartbeat (pacemaker), located in right atrial wall
AV node (Atrio-ventricular node): delays impulse - 0.1s, allows atria to contract fully
Bundle of His: splits impulse into left/right sides
Bundle branches: carry impulse down septum
Purkinje fibres: spread impulse through ventricles -> causes contraction
Conduction system - coordinates contraction
The cardiac cycle
Cycle length - 0.8 seconds per beat
Phases:
Diastole (0.4s) - relaxation of atria/ventricles -> blood flows into heart
AV valves open, SL valves closed
Atrial systole (0.1s) - atria contract -> blood into ventricles
AV valves still open
Ventricular systole (0.3s) - ventricles contract -> blood into arteries
AV valves close, SL valves open
Hear rate, stroke volume + cardiac output
Definitions: - Heart rate