question_answer 75)

  What is cancer? How is a cancer cell different from the normal cell? How do normal cells attain cancerous nature?

Answer:

                  An abnormal and uncontrolled division of cells is termed as cancer. Genes called cellular oncogenes (c-onc) or proto-oncogens present in normal cells when activated under certain conditions lead oncogenic transformation of the normal cells leading cancer. A cancer cell is different from the normal cell in following ways

Cancer cell	Normal cell
Cancer cells divide in an uncontrolled manner. The cells do not show contact inhibition. Life span is indefinite	Normal cells divide in a controlled manner. The cells show contact inhibition Life span is definite