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 is made of gases that are essential for photosynthesis and other life activities? Answer: atmosphere

A: The atmosphere is made of gases that are essential for photosynthesis and other life activities.
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Q: Question: What type of tissue is made up of cells that have the unique ability to contract? Answer: muscle tissue

A: Muscle tissue is made up of cells that have the unique ability to contract, or become shorter. Muscles attached to bones enable the body to move.
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Q: Question: Groupings of related organs in the human body are referred to as "organ" what? Answer: systems

A:
Human organ systems work together to carry out many of their functions. The skeletal and muscular systems are no exception.
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