The important features of human heart are:
1.)Human heart is four chambered.
2.)The heart is covered by a double-layered tissue known as pericardial tissues.
3.)In between the two layers of pericardial tissues lies pericardial fluid.
4.)The Right Auricle and Ventricle carry deoxygenated blood while the Left Auricle and Ventricle carry oxygenated blood.
5.)The auricles and ventricles undergo systole(contraction) and diastole(relaxation)alternatively and both rest for 0.40 sec.
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