9781422276112

Systems of the Human Body • The skeletal system supports the human body and protects its internal organs. • The muscular system allows the human body to move. • The nervous system carries messages between the body and the brain. • The circulatory system moves substances to and from the body cells. • The digestive system digests and extracts energy and nutrients from food. • The respiratory system controls the gaseous exchange in the body. • The endocrine system controls the secretion of hormones from ductless glands. • The immune system defends the body against diseases. • The urinary system includes organs such as the kidneys and the large intestine. They work together to remove unwanted, undigested waste. • The reproductive system includes organs that regulate the sexual functions of the body.

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