. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 280 J OX AT MAX ['. GREEX \vas followed by a 30-minute distilled water wash. The preceding steps were car- ried out at 0° C. with continuous agitation. Immediately after the final washing, the tissue was peeled from the exoskeleton and was cut into pieces 1 mm2. Dehydration in a graded series of cold acetone-H0O mixtures followed. The tissue remained in \OQ(/c acetone at room temperature for 8 minutes with two changes. Infiltration in a graded series of epon-araldite-acetone mixtures to lOO'/o epon- araldite (:1) followe
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 280 J OX AT MAX ['. GREEX \vas followed by a 30-minute distilled water wash. The preceding steps were car- ried out at 0° C. with continuous agitation. Immediately after the final washing, the tissue was peeled from the exoskeleton and was cut into pieces 1 mm2. Dehydration in a graded series of cold acetone-H0O mixtures followed. The tissue remained in \OQ(/c acetone at room temperature for 8 minutes with two changes. Infiltration in a graded series of epon-araldite-acetone mixtures to lOO'/o epon- araldite (:1) followed over a three hour period (Voelz and Dworkin 1962). The tissue was flat-embedded in epon-araldite and polymerized at 60° C. for 72 hours. Sections /j. thick were prepared with a Porter-Blum MT-2 ultratome. Sections were floated on water and attached to pre-cleaned microscope slides. Autoradiographs were prepared from this material as previously described. RESULTS Green, 19641) found that /';/ 1'iro incorporation of 14C-tyrosine into melanin \vas independent of the degree of dispersal of the pigment granules within the melano- phore. This does not show that melanin synthesis occurs within the melanophores. The present study was designed to identify the site of melanin synthesis in Uca Autoradiographs prepared from the epidermis indicate that melanin syn- thesis occurs only within the melanophore. Figure 1 is a low power view of epidermis, containing a melanophore with dis- persed pigment. A grid was superimposed over this photograph and the silver grains in 20 randomly chosen squares over a melanophore process were counted. Similarly silver grains located in 20 squares which were not over a melanophore process were counted. Squares outside of the boundary of the melanophore had ± (mean ± ) grains per square as compared with ± grains per square over a portion of a melanophore. These counts differ significantly (P < —Studen
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
