Why is blood circulation across the human heart considered as a double circulation? (1 Mark)
The blood circulation in human heart is called double circulation since the blood passes through the heart twice in one complete cycle of the body i.e. once through the right half in the form of deoxygenated blood to lungs (pulmonary circulation) and next through the left half in the form of oxygenated blood to all body parts (systemic circulation).
(1 Mark)