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What is double circulation? How blood circulation is done in fishes having 2- chambered heart? |
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Answer» The heart is a key organ for blood circulation and double circulation provides an effective way of circulation. In double circulation, blood follows two routes- one for oxygenated blood and other for deoxygenated blood. The blood vessels responsible for carrying out double circulation: • Pulmonary artery: it takes deoxygenated blood to the lungs. • Aorta: it carries oxygenated blood to body tissues • Pulmonary vein: it carries oxygenated blood • Vena cava: it takes deoxygenated blood. Fish have a single circuit for blood flow and a two chambered heart that has only a single atrium and a single ventricle. Because blood leaves the gills and immediately circulates to the rest of the body, the heart does not require additional chambers. The blood then arrives back at the atrium. This is called systemic circulation. |
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