instruction:
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: What is the main function of the cardiovascular system? Answer: to transport
answer:
Many ecosystems have changed because of human actions. The human species is responsible for a range of environmental problems.

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Question: What occurs when two wave crests overlap? Answer: constructive interference
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Constructive interference occurs when two wave crests overlap, doubling the wave amplitude at that location.

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Question: Fatty acids, triglycerides, phospholipids, and steroids are examples of what? Answer: lipids
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Lipids are a diverse class of relatively nonpolar biomolecules that generally do not dissolve well in water. Common types of lipids include fatty acids, triglycerides, phospholipids, and steroids.