The invention relates to a disposable cassette as a replaceable component of an analysis instrument comprising fluid paths integrated in the cassette. In accordance with the invention, at least one container with a liquid, for example a calibration fluid, is integrated in a liquid-tight manner in the disposable cassette. An integrated spike is provided in the disposable cassette, for example as apivotable rocker hook, via which the pouch can be opened so that the liquid can be guided into the fluid paths of the disposable cassette.