blood circulation steps

Step 1

Right atrium recieves blood from superior and inferior venae cavae and coronary sinus

Step 2

Blood flows from right atrium through open tricuspid (right AV) valve into right ventricles

Step 3

Pulmonary valve is pushed open when right ventricle contracts, allowing blood to enter pulmonary trunk

Step 4=

Blood travels within right and left pulmonary arteries to alveolar capillaries in lungs, where CO2 is unloaded and O2 is loaded

Step 5

Blood travels within right and left pulmonary veins from lungs to left atrium

Step 6

Blood left atrium flows through open mitral (left AV) valve into left ventricle

Step 7

Aortic valve is pushed open when left ventricle contracts, allowing blood to enter aorta

Step 8

Blood flows from aorta to systemic capillaries where O2 is unloaded and Co2 is loaded

Step 9

Blood returns to right atrium from body tissues and myocardium via venae cavae and coronary sinus