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.
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Question: Question: Stis are diseases caused by what that spread through sexual contact? Answer: pathogens

Answer: STIs are diseases caused by pathogens that spread through sexual contact. Abstinence from sexual activity and other risk behaviors is the only completely effective way to prevent the spread of STIs.


Question: Question: What substances, which serve as catalysts, are involved in most of the chemical reactions that take place in organisms? Answer: enzymes

Answer: Enzymes are involved in most of the chemical reactions that take place in organisms.


Question: Question: The risk of what is raised by overexposure to the sun? Answer: skin cancer

Answer:
It might be fun to lay out in the sun like these two girls are doing. But getting too much sun can be very dangerous. Overexposure to sunlight raises your risk for skin cancer.


