can you explain what cancer is and why it happens.
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Cancer is a disease that occurs when cells in our body begin to grow and divide uncontrollably. Unlike normal cells which grow in an orderly pattern, cancer cells multiply rapidly and can invade healthy tissues around them.
In a healthy body, cells function in a highly controlled manner. They follow precise instructions encoded in their DNA, which tells them when to grow, when to divide, and when to die. This orderly process maintains the balance and health of our tissues.
Cancer begins when DNA becomes damaged or mutated. These mutations change the instructions that control cell behavior. DNA damage can be caused by various factors including UV radiation, chemicals, viruses, or random errors during cell division.
When DNA mutations accumulate, cells lose their normal growth controls. They begin to multiply rapidly and uncontrollably, forming a mass called a tumor. These cancer cells can invade and destroy surrounding healthy tissues.
Cancer can be caused by various factors. About 5 to 10 percent of cancers are inherited through genes. Environmental factors like UV radiation and chemicals, lifestyle choices such as smoking, viral infections, and random errors during cell division all contribute to cancer development.