Summary
The major difference between freeze-etched illuminated and non-illuminatedPhlyctochytrium zoospores was in the plasmalemma. The illuminated spores had abundant 15–18 nm freeze fracture particles on the PF surface of the plasmalemma in a region external to the rumposomal complex. Non-illuminated spores show fewer and smaller (6–12 nm) freeze fracture particles on the PF surface of the plasmalemma external to the rumposomal complex. Both illuminated and non-illuminated zoospores have rumposomal complexes, nuclear caps, mitochondria, nuclei, and a variety of cytoplasmic vesicles. The nuclear pores were not randomly distributed over the surface of the zoospore nucleus. Micrographs of nuclei in developing sporangia indicate pore formation in the region of the nuclear pockets.
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A portion of this study was carried out at the Virginia Institute of Marine Science, Gloucester Point, Virginia.
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Kazama, F.Y., Schornstein, K.L. A freeze-etch study of the phototactic zoospores ofPhlyctochytrium sp., a marine fungus. Protoplasma 91, 143–156 (1977). https://doi.org/10.1007/BF01276729
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DOI: https://doi.org/10.1007/BF01276729