. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. EFFECTS OF ANOXIA ON 161 Table III Comparison between anoxic and normoxic metabolic rates (mean ± ) by juveniles oj "Crassostrea virginica (30 mg dry tissue mass) at 15°C(n = 9) and22°C(n = .V 15°C 22°C Normoxia Respiration rate (^molesO2h ') ± ± Respiration rate (J h ') ± + Anoxia Heat dissipation rate (J h ') Anoxic rate as a proportion of normoxic rate + + kJ mol ' O2 and then declined to -486 kJ mol ' O: after 6 h. Effect
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. EFFECTS OF ANOXIA ON 161 Table III Comparison between anoxic and normoxic metabolic rates (mean ± ) by juveniles oj "Crassostrea virginica (30 mg dry tissue mass) at 15°C(n = 9) and22°C(n = .V 15°C 22°C Normoxia Respiration rate (^molesO2h ') ± ± Respiration rate (J h ') ± + Anoxia Heat dissipation rate (J h ') Anoxic rate as a proportion of normoxic rate + + kJ mol ' O2 and then declined to -486 kJ mol ' O: after 6 h. Effect oj hypoxia and anoxia on the rate ofingestion The general response of prodissoconch and pediveliger larvae to hypoxia and anoxia was a reduction in the pro- portion of the larvae actively feeding and ingesting mi- crospheres over 24 h exposure, and a marked decline in the rate ofingestion of microspheres within the initial 2- 3 h (Fig. 4A-D; Fig. 5A-D). Although the data for pro- dissoconch larvae were more variable, with the percent- age of larvae feeding being inexplicably depressed at cer- tain times (, control or time zero and h for P0, of kPa, Fig. 4A; h and 4 h for P0; of kPa, Fig. 4C), the reduction in the rate ofingestion was small compared to the reduction shown by pediveligers under hypoxic conditions. The ingestion rates by prodis- soconch larvae were generally between 5 and 8 micro- spheres larva"' per 10 min under normoxic conditions. Ingestion rates declined to about 2 microspheres lar- va"' 10 min ' after 2-3 h of hypoxia (< kPa) and these rates were then maintained for the 24 h of exposure to hypoxia (Figs. 4A-D). However, prodissoconch larvae exposed to anoxia showed no evidence ofingestion after 10 h of anoxia (Fig. 4D). Pediveligers also showed a gradual decline in the pro- portion of larvae ingesting microspheres with increasing duration of exposure to hypoxic and anoxic conditions (Figs. 5A-D). Under nor
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
