A five sentence paragraph describing a human organ system include a main idea, supporting details, and a concluding statement

The endocrine system is an essential organ system.  It produces and secretes hormones, and regulates the amount of each hormone released. The endocrine glands release hormones; these hormones help control many things including growth and development, reproduction, and metabolism. Without the endocrine system, we would not function properly. To conclude, the endocrine system is a very important human organ system.

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