Measures of Respiratory Activity With Resting Cells. ∗

Conclusions

The Q_o2(N) has much to recommend it as the most suitable measure of respiration activity. With the rhizobia, for example, not only does it show the least variation of the measures employed, independent of the composition of the medium used for growth of the cells, but also it rests upon a Kjeldahl analysis which is probably the easiest and most accurate of the determinations made. As long- as respiration of washed cells remains linear with time, assimilation of a portion of the substrate should not seriously interfere with interpretation of the results.