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The thrapple in the gastrointestinal seestem

The thrapple or hause(-pipe) is the pairt o the gastrointestinal seestem atween the mooth an the painch.

The thrapple is lined wi muscle. This muscle pushes the baw o fuid doun intae the painch. The thrapple can contract or hove for tae allou for the passage o fuid.