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: What contains most of the structures found in skin? Answer: dermis

A: Structures of the Dermis. The dermis contains most of the structures found in skin.
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Q: Question: What changes nitrogen gas from the atmosphere to nitrogen compounds that plants can absorb? Answer: bacteria

A: Bacteria change nitrogen gas from the atmosphere to nitrogen compounds that plants can absorb.
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Q: Question: What preventative measure is often delivered by injection into the arm? Answer: vaccine

A:
Figure 42.18 Vaccines are often delivered by injection into the arm. (credit: U. Navy Photographer's Mate Airman Apprentice Christopher D. Blachly).
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