. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 366 EVANS, BEAMS AND SMITH Effect of pH on the Jelly.—Inasmuch as acid sea water has been used to remove the jelly from the eggs (Harvey, 1939; Just, 1939; Tyler, 1940; Tyler and Fox, 1940), it seemed of interest to determine whether the radiation might increase the acidity of the egg medium enough to account for the removal of the jelly. One of the first steps in this in- vestigation was to determine what pH range was effective in removing the jelly. It was found that at a pH of , or below, nearly all of the eggs lost th
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 366 EVANS, BEAMS AND SMITH Effect of pH on the Jelly.—Inasmuch as acid sea water has been used to remove the jelly from the eggs (Harvey, 1939; Just, 1939; Tyler, 1940; Tyler and Fox, 1940), it seemed of interest to determine whether the radiation might increase the acidity of the egg medium enough to account for the removal of the jelly. One of the first steps in this in- vestigation was to determine what pH range was effective in removing the jelly. It was found that at a pH of , or below, nearly all of the eggs lost their jelly within five minutes. Jelly alone was placed in solu- tions buffered at different pH values and it was found that at pH the Janus green test was negative, and at pH it was very faint, but 8 0 7 5 7 0 X Q_ 6 5 6 0. 0 20 40 60 80 100 DOSAGE IN 1000 ROENTGENS I 20 FIG. 2. Effects of Roentgen radiation on the pH of certain media. Curve one—jelly in medium buffered at pH Curve two—jelly in sea water. Curve three—jelly in NaCl-KCl mixture. Curve four—eggs alone in the NaCl-KCl mixture. Curve five—supernatant fluid from cytolyzed eggs. at pH to pH the test was strongly positive. These results indi- cate that a marked change in the properties of the jelly is brought about by solutions whose pH values are as low as This finding is in accord with that of Tyler (1940), who used solutions of pH to dissolve the jelly. Effect of the Radiation on tJie pH of the Solution.—Sea water was irradiated and in two experiments where the dosage was 121,000 r the maximum lowering was only of a pH unit. Fresh eggs placed in such irradiated water retained the jelly layer intact. Irradiation of freshly-shed eggs in sea water apparently produced some acidity in the medium. In a representative experiment the pH. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
