Given a scientific question and its correct answer, generate supporting facts for the answer. This supporting fact can be an explanation for the answer to the given question.

Q: Question: Cigarettes are a major source of what kind of chemical substances linked with cancer? Answer: carcinogens

A: Courtesy of the CDC/Debora Cartagena. Cigarettes are a major source of chemical carcinogens .
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Q: Question: Organisms cannot live alone, needing other organisms to survive; what is this relationship called? Answer: interdependence

A: Organisms are not independent, they are interdependent . They cannot live alone; they need other organisms to survive. The same is true for species. All species need other species to survive.
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Q: Question: Red bone marrow, tonsils, spleen, and thymus gland are considered organs of what system? Answer: lymphatic

A:
The lymph organs are the red bone marrow , tonsils , spleen , and thymus gland . They are described below ( Figure below ).
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