Final answer:
Cancer cells are more vulnerable to radiation and toxic chemicals due to their inability to arrest the cell cycle for DNA repair, often a result of mutated proteins like p53. These cells continue dividing uncontrollably, forming tumors and outcompeting healthy cells for nutrients and space.
Step-by-step explanation:
Cancer cells tend to be more susceptible to the damaging effects of radiation and toxic chemicals because they lack the ability to arrest the cell cycle and make the necessary repairs.
In a normal cell, if DNA damage occurs, the cell cycle is arrested to allow repair mechanisms to fix the damage. Proteins like p53 play a crucial role in this process by preventing the cell from dividing until the damage is repaired.
In cells where p53 or other regulatory proteins are mutated, this checkpoint fails, allowing the cell to continue dividing without repair, leading to the accumulation of further mutations and the development of cancer.
Another consequence of this failed regulation is that cancer cells often cannot form proper connections, like Gap Junctions, with adjacent cells, contributing to their uncontrolled growth.
Damaged cells that continue to divide can rapidly outgrow normal cells, using up vital nutrients and space, eventually forming a tumor and damaging tissues and organs.