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Due to the lapse in government funding, only websites supporting excepted functions will be updated unless otherwise funded. As a result, the information on this website may not be up to date and the agency will not be able to respond to inquiries until appropriations are enacted.

Updates regarding government operating status and resumption of normal operations can be found at

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Inside your body

Your body is fantastic! It's a great idea to learn how your body works. That way, you can help protect it from problems and appreciate it when all goes well.

What are the major systems of your body? Check them out here.

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Content last reviewed April 15, 2014
Page last updated May 23, 2014