Definition: "The type of circulation pathway in which venous blood is passed
<span>from the right atrium of the heart through the right ventricle and
</span> pulmonary<span> arteries to the lungs where it is oxygenated and its return via the </span>pulmonary<span> veins to enter the left auricle and participate in the systemic </span>circulation"<span>.
Explanation:
There are two circulatory path in cardiovascular system namely pulmonary circulation and systemic circulation. Pulmonary circulation path allows for blood circulation through lungs for oxygenation while systemic circulation allows for transport of oxygenated blood to all parts of the body.
Pulmonary Circulation Pathway: Pulmonary circulation pathway consist of:
1. Superior and inferior vena cava:
De-oxygenated blood from lower parts of the body enter to right atrium through inferior vena cava. Similary, deoxygenated blood from upper parts of the body enter to right atrium through superior vena cava.
2. Right atrium and right ventricle:
From right atrium the blood passes to right ventricle through tricuspid valve.
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3. Pulmonary artery: Afterwards, the blood enters the pulmonary artery via the pulmonary valve. The pulmonary artery divides into two arteries with one artery entering the right lung and the other artery entering the left lung. When the blood reaches the lungs through the left and right pulmonary arteries, it moves over alveoli via the capillary beds. </span><span>
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4. Left atrium and left ventricle: After the blood gets oxygenated, it moves back to the heart and this time moves into the left atrium, completing the pulmonary circulation path.</span><span>
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