Fig. 1. A representative respirometric recording showing the measured variables as obtained from the analyzers: CO₂ production, in parts per million (p.p.m., in black), O₂ consumption, in fractional scale (in red) and H₂O production, in parts per thousand (p.p.t., in blue). A detailed trace of CO₂ and O₂ is shown in the zoom. The CO₂ analyzer is accurate enough to show, in some cases, the changes in gas concentration arising from respiratory movements.