. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. ,60**,. FIGURE 1. Diagram showing the arrangement of leg regenerate explants in the culture chamber. Epithelial cells fee) surround the leg regenerate (Ir) while glial cells (gc) and axon fibers fax) emerge from the stump of the fifth mesothoracic nerve. The entire prepara- tion is held in place by a strip of dialysis membrane (ds). FIGURE 2. Glial cells with accompanying axon fibers emerging from the nerve stump of a cockroach leg regenerate. Dark contrast phase; 25 days in vitro. FIGURE 3. Diagrammatic representation of th
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. ,60**,. FIGURE 1. Diagram showing the arrangement of leg regenerate explants in the culture chamber. Epithelial cells fee) surround the leg regenerate (Ir) while glial cells (gc) and axon fibers fax) emerge from the stump of the fifth mesothoracic nerve. The entire prepara- tion is held in place by a strip of dialysis membrane (ds). FIGURE 2. Glial cells with accompanying axon fibers emerging from the nerve stump of a cockroach leg regenerate. Dark contrast phase; 25 days in vitro. FIGURE 3. Diagrammatic representation of the photograph in Figure 2. Axon fibers (ax) lying on the surface of glial cells (gc) extend out onto the surface of the cover glass. The granules that surround the nucelus (nu) probably contain glycogen. The chambers were emptied and refilled with the medium in which the glands had been incubated, and the gland itself was discarded. After 6 more days of incubation, the chambers were again checked, and if glial cells and axons were present, the explant was scored as positive; if they were not present, it was scored as negative (Fig. 2). Three sets of controls were used. In one set, fresh medium was added after the initial reading; the second set contained fresh medium to which was added 5', fetal calf serum; and in the third set, 1 cc of medium was added in which a 2-mm cube of cockroach muscle tissue had been incubated. The results obtained with gland incubates were tested against the controls by using the test for the dif- ference between two sample proportions given by Goldstein (1964); significance was set at P -- RESULTS Control scries If the results of these experiments were to be meaningful, we first had to be sure that the changes in occurrence of regenerative nerve growth in the experi- mental chambers were not affected perceptibly by either nutrient substances or nonspecific growth factors released into the medium by the glands being tested. Therefore we ran a ser
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
