Levels of Organization

Atoms: tiny building blocks of matter

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Cells: smallest units of living things

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Tissues: consists of groups of similar cells that have a common function

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Organs: structure composed of at least 2 tissue types that perform a specific function for the body

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Organ Systems: organs that cooperate and work closely together to accomplish a common purpose

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Organisms: sum total of all structural levels working in unison to promote life