. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 324 K. SLAMA AND M. HODKOVA to the 5th or 6th day thereafter. Later treatments of the non-feeding last instar larvae had no effect on OL. consumption of the prepupal stages. The respiratory quotients determined by the indirect Warburg method re- vealed somewhat lower ratios in hypermetabolic larvae () in comparison with the equally old untreated larvae (). This suggests that simultaneously with the almost 10-fold increase of O^ consumption during hypermetabolism, the output of CO-2 was also enormously increased. De
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 324 K. SLAMA AND M. HODKOVA to the 5th or 6th day thereafter. Later treatments of the non-feeding last instar larvae had no effect on OL. consumption of the prepupal stages. The respiratory quotients determined by the indirect Warburg method re- vealed somewhat lower ratios in hypermetabolic larvae () in comparison with the equally old untreated larvae (). This suggests that simultaneously with the almost 10-fold increase of O^ consumption during hypermetabolism, the output of CO-2 was also enormously increased. Dependence of Jiypcrnictabolisin on nutrition Preliminary experiments revealed that hypermetabolism was seriously limited or absent when the treated larvae were deprived of food. We have now performed another series of experiments using non-feeding and immobile larvae which had been ligated behind the head capsule. According to Slania ct al. (1974) the larvae of D. z'ltplinits can be ligated at any time in the 6th instar and still develop into headless pupae and adults. Moreover, when treated with juvenoids the ligated larvae were subjected to the same inhibition of metamorphosis as were normal feeding larvae. It was therefore advantageous to use ligated larvae for OL> con- sumption measurements because variations due to differences in locomotory activity and food digestion were thereby avoided. Figure 3 presents a comparison of O2 consumption curves of normal last instar larvae and of individuals ligated shortly after ecdysis. In both instances the larvae 0"|.2 \ O-- o 8 10 DAYS FIGURE 3. (X consumption of the last instar larvae which were ligated behind the head just after ecdysis (broken line; n = 5 specimens) or ligated and simultaneously treated with 50/jiig/specimen of the juvenoid (full line; n = 6 specimens). The dotted line is taken from Fig. 1 and shows O- consumption of normal feeding larvae. Small rings indicate ecdysis or cryptoecdysis, r
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
