The overall purpose of multiple body systems working together within an organism is to maintain homeostasis, which is the ability of the body to regulate and maintain stable internal conditions despite external changes. By working together, different body systems ensure that the organism is able to function properly and respond effectively to various internal and external stimuli, ultimately allowing the organism to survive and thrive in its environment.

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Multiple body systems work together to maintain homeostasis, ensuring the organism can function properly and respond effectively to stimuli.