Question

Cells are the basic units of life. They undergo a natural life and death cycle called mitosis and apoptosis. Under normal circumstances, normal cells grow, divide and rest. But cancerous cells do not rest after they grow and divide - they continuously replicate. However, proliferation of cells do NOT always result in cancer, but instead form benign tumors. In your own words, explain the difference between benign and malignant cells. Include the word "metastasis" in your explanation.

Answer 1

As cancer is the uncontrolled division of any cell . Cancerous cell have some problem in cell cycle regulatory mechanism(cell cycle check points).

Generally cancer tumors are of two types benign and melignant based on mobility of cancerous cells in body.

We know that cancer cell devide uncontrolled and contineous.cell division process require energy in form of carbohydrates , amino acids and vitamins etc which is supplied through blood and most important oxygen supply and carbon dioxide removal from cells dependent on blood supply.

Now in benign tumor there is no blood supply because there is no reached of blood vessels so no oxygen supply ,no carbondioxide removal ,no carbohydrates supply so not able to move to other organs of body. So these type of tumor remain dormant without nutrients and doesn't develop cancer until unless it gets blood supply

In malignant tumor there is proper blood supply to tumor .Blood vessel formation is induced by VEGF factor secreted by tumor cells. Blood supply provide nutrient as well as help the cancerous cells to move to there organs of body ,now these cancerous cells move and proliferate in other organ also and cause multi organ failure .

Metastasis is the movement of cancerous cells from tumor to other organs of body through blood circulation.

malignant tumor is more life threatening then benign tumor.