Explain/ describe the pumping mechanism of the mammalian heart.

Answer:

i)Diastole-The ventricles and auricles/ atria relax; increasing their volume; decreasing pressure; the cuspid valves open; while the semi-lunar valves close; Oxygenated blood flows from the right auricle/atrium; to the right ventricle; while deoxygenated blood flows from the left auricle/ atrium; to the left ventricle;
ii)Systole-the auricles contract; while ventricles remain relaxed; this decreases the volume of auricles; increasing pressure; higher pressure causes the cuspid valves to open; blood flows into the ventricles; ventricles contract causing the semi-lunar valves to open while the cuspid valves close; blood flows out of the heart to the lungs; through the pulmonary artery; and to all parts of the body through the aorta;

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