Social change is an important modification in the structure of a society. Social change can be applied to numerous aspects of a society such as economic, political, cultural, ethical and identity issues of a community. These changes may occur in the values, traditions, norms or material manifestations of the community. The changes in the forms of government, the variation in the systems of customs, the evolution of the economic programs, the alteration of the values of behavior are clear patterns of social change.
Blood enters on the left side of the heart through the pulmonary veins and enters the left atrium. Then passes to the mitral(bicuspid valve) to enter the left ventricle.
