Final answer:
Cancer is a disease caused by unregulated cell division. Abnormal cells divide faster than normal cells, forming tumors. This can damage tissues and organs and eventually lead to death.
Step-by-step explanation:
Cancer is a disease that occurs when the cell cycle is no longer regulated. This may happen because a cell's DNA becomes damaged. Damage can occur due to exposure to hazards such as radiation or toxic chemicals. Cancerous cells generally divide much faster than normal cells. They may form a mass of abnormal cells called a tumor. The rapidly dividing cells take up nutrients and space that normal cells need. This can damage tissues and organs and eventually lead to death.