. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. HYPERBARIC OXYGEN AND DEVELOPMENT 347 100 9C- 80- 70- 50 30— 20. II G R 36 G R Pr PI 48 G R Pr PI 60 HOURS R Pr PI 72 G R Pr PI 84 1. Bar graphs showing the per cent of embryos at given developmental stages at various times following removal of the embryos from 3 AA oxygen at 36 hours post-fertiliza- tion age. Abbreviations are: G^gastrula; R—regressing gastrula; Pr—prism stage; PI— pluteus. A minimum of 200 embryos was counted at each age. Scries 2 experiments Embryos were exposed to HBO for 12, 24, 36 or 48 hou
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. HYPERBARIC OXYGEN AND DEVELOPMENT 347 100 9C- 80- 70- 50 30— 20. II G R 36 G R Pr PI 48 G R Pr PI 60 HOURS R Pr PI 72 G R Pr PI 84 1. Bar graphs showing the per cent of embryos at given developmental stages at various times following removal of the embryos from 3 AA oxygen at 36 hours post-fertiliza- tion age. Abbreviations are: G^gastrula; R—regressing gastrula; Pr—prism stage; PI— pluteus. A minimum of 200 embryos was counted at each age. Scries 2 experiments Embryos were exposed to HBO for 12, 24, 36 or 48 hours and were then re- moved to air and subsequent development was observed. (a) Embryos removed at 12 or 24 hours. Embryos exposed to HBO during the first 12 hours of development only were not altered morphologically, and de- veloped at the same rate as did controls. Development was retarded in embryos exposed to HBO for the first 24 hours of development only, retardation being evi- denced between the time of removal (mesenchyme blastula stage) and pluteus for- mation. Xo abnormal morphological alterations were detected, however. By 60 hours, nearly all such embryos had reached young pluteus stage. This represents a delay of 12 hours beyond the time at which all control embryos reached this stage (48 hr). (b ) Embryos removed at 36 hours. (See Fig. 1) At the time of removal, the embryo population consisted almost entirely of morphologically normal gastrulae, plus blastula-like forms designated "regressing ; No prism stages were seen; by 48 hours following removal, 17% of the population consisted of prisms, and 3% of normal young plutei. The relative numbers of prism and pluteus stages which were seen increased through 84 hours, when the experiment was terminated with over 90% of the embryos beyond gastrulation stage, in prism or pluteus. Please note that these images are extracted from scanned page images that may have been digitally enhanced fo
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
