The answer is; cancer occurs due to unregulated cell division
This causes them to proliferate causing a mass of cells and affect neighboring tissues. The cells are usually undifferentiated and therefore do not function properly as tissue. This unregulated division is due to malfunction of the tumor suppressor gene that is significant in cell cycle regulation and apoptosis.
Answer: germ theory
Explanation: Germ theory of disease is a theory in biology. It says that small organisms (called germs), also known as microbes, cause diseases. Most, but not all diseases are infectious diseases. The germ theory states that small organisms cause a reaction in the body of those who are infected. The body's reaction to infection is called a disease.
Reference: Wikipedia
Answer:
Human impact on the environment or anthropogenic impact on the environment includes changes to biophysical environments and to ecosystems, biodiversity, and natural resources caused directly or indirectly by humans, including global warming, environmental degradation (such as ocean acidification), mass extinction and etc...
Humans impact the physical environment in many ways: overpopulation, pollution, burning fossil fuels, and deforestation. Changes like these have triggered climate change, soil erosion, poor air quality, and undrinkable water.
