. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. HOW SEA STARS OPEN BIVALVES 115 homogenize! in the cold. Enough sea water or distilled water was added to make up 10(/r solutions relative to the wet weight of the organs used. (Other concen- trations were tested and, generally, yielded similar results.) Extraction was al- lowed to proceed for varying times (5 minutes to 48 hours) and the tissue debris was removed by filtration or centrifugation. Other extraction methods were em- ployed to test the possibilities that the alleged toxin might be only poorly soluble in water, t
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. HOW SEA STARS OPEN BIVALVES 115 homogenize! in the cold. Enough sea water or distilled water was added to make up 10(/r solutions relative to the wet weight of the organs used. (Other concen- trations were tested and, generally, yielded similar results.) Extraction was al- lowed to proceed for varying times (5 minutes to 48 hours) and the tissue debris was removed by filtration or centrifugation. Other extraction methods were em- ployed to test the possibilities that the alleged toxin might be only poorly soluble in water, that it might occur in bound form, or that it might require activation. Thus, some extractions were made with fat solvents, some extracts were dialyzed, others were frozen and thawed before use, and some were mixtures of homogenates from different rff I FIGURE 1. Constant stress apparatus. Each 800-gram weight was suspended by a cord passing over a ball-bearinged pulley to a double hook inserted into notches filed in the beak of the mussel shell. Another hook, also made from two bent pins, was soldered to the bottom of the pan and passed through the same notches. Gapes were measured by means of a calibrated metal triangle which could be slipped in between the valves near the hooks. All extracts were tested on the common sea mussel, M\tilus cdulis. In most cases ml. of the clear extract was injected by means of hypodermic syringe into> the mantle cavity or ml. was injected directly into the posterior adductor muscle by way of a notch filed in the shell's dorsal edge. Each mussel had been pre-tested to insure that its physiological condition was approximately comparable to that of the other experimental animals. The pre-test was accomplished by exerting a pull of 800 grams on the valves for five minutes; only mussels which gaped less than one mm. were used for injection tests. After being injected, each mussel was subjected to a steady pull of 800 grams on its
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
