Part 1 of Essay
The word Tumor simply means abnormal growth. Frequently this term is incorrectly used interchangeably with cancer. However, tumor may refer to a benign (non-cancerous) or malignant (cancerous) growth. Both benign and malignant result from the abnormal growth of cells. Normal cells reproduce in an order controlled fashion. ....

Part 2 of Essay
.... and this causes the development of a tumor. Whether or not the tumor will be cancerous or not is determined at this point by a process called differentiation. Differentiation is the process by which normal cells undergo physical and structural changes as they develop to form different tissues of the body. Differentiated cells specialize in multiple physiological functions. For example, a highly differentiated cell like a nerve cell still shares many features in common with all cells (i.e. nucleus, cell membrane ....