The journey begins in the bones, where the blood cells are made. The red blood cells move around within capillaries.
The deoxygenated red blood cells makes its way to the heart in the vena cava. After it made its way to the right atrium, the right atrium contracts and pushes the red blood cell to the to the right ventricle through the tricuspid. .
Through the semi lunar the right ventricle does its contraction and pushes the red blood cell out of the heart.
Now that the red blood cell has reached the lungs with the help of pulmonary artery, it picks up oxygen and makes its way back to the left atrium through the pulmonary vein.
The left atrium contracts, pushes the red blood cell through the bicuspid to the left ventricle.
Next, the left ventricle contracts and pushes the red blood cell through the semilunar valve into the aorta to exit the heart.
The journey follows with the red blood cell travelling through the aorta into the kidneys track and lower limbs.
Lastly, the deoxygenated blood travels back up to the heart through the vena cava. The blood cells repeat this journey and process over and over again.