. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 0 50 100 150 200 Grams/liter Figure 1. Osmolality of NaCl solutions and Mono Lake water of equal salt content on a g/1 basis. Dotted arrows indicate that a A/ (117 g/1) NaCl solution is the osmotic equivalent of about 150 g/1 Mono Lake water. NaCl data are from Weast (1983). Data for Mono Lake water are from two sources using different methods: (squares) our data, obtained by freezing point depression; (circles) Herbst and Dana (1980), determined by vapor pressure « To o O) E 6) ft of days Figure 2. Trehalose
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 0 50 100 150 200 Grams/liter Figure 1. Osmolality of NaCl solutions and Mono Lake water of equal salt content on a g/1 basis. Dotted arrows indicate that a A/ (117 g/1) NaCl solution is the osmotic equivalent of about 150 g/1 Mono Lake water. NaCl data are from Weast (1983). Data for Mono Lake water are from two sources using different methods: (squares) our data, obtained by freezing point depression; (circles) Herbst and Dana (1980), determined by vapor pressure « To o O) E 6) ft of days Figure 2. Trehalose (solid lines) and glycerol (broken lines) contents of cysts incubated under the following conditions: 4°C. aerobic (triangles): 4°C, anaerobic (closed circles); 14°C, aerobic (open circles); 14°C. an- aerobic (squares). The 4°C. aerobic incubation is the only treatment which permitted both activation and hatching; the cysts were not sampled after 90 days because the majority of them had hatched. Note the sig- nificant decline in trehalose as glycerol increases. The other three incu- bations exhibited no hatching: cysts in the 4°C, anaerobic incubation could break diapause, but could not hatch in the absence of oxygen. Points are x ± SD. n = 3. Having shown that the synthesis of glycerol proceeds with hatching, we incubated cysts in several salinities of MLW to determine the effect of salinity on carbohydrate metabolism. Simultaneously, we monitored termination of diapause and hatching. Increasing salinities resulted in faster synthesis of glycerol (Fig. 3a), while trehalose breakdown is slower at higher salinities (Fig. 3b). Figure 3c shows that, at the lowest salinity (50 g/1), glycogen is synthesized in addition to glycerol, suggesting that at this salinity some of the trehalose is being converted to gly- cogen. However, glycogen shows net degradation in the higher salinities, indicating that an osmotic regulatory mechanism may control the amount of glycerol and gly-
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
