ISSN:
1615-6102
Keywords:
Diatom
;
Motility
;
Mucopolysaccharide
;
Secretion
;
Staining
;
Ultrastructure
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary Generation of movement in benthic diatoms is thought to be intimately associated with secretion at the raphe, a slit in the silica cell wall. The presence and distribution of extracellular substances and their source was investigated cytochemically by transmission electron microscopy. Extracellular material, possibly-acid mucopolysaccharide, was observed consistently within the entire length of the raphe of both valves and also as a sheath enveloping the silica frustule. Such quantities of extracellular material are absent in conventionally fixed motile diatoms. Numerous cytoplasmic vesicles, with fibrillar contents, distributed peripherally but concentrated along the raphe and at the cell poles, react strongly with a polysaccharide specific stain; their distribution in the cell and polysaccharide content suggest these may be the source of raphe and sheath material. Results support the most recent theories on the mechanism of locomotion in outline only; the details cannot be clarified. Localization procedures using alcian blue and silver staining of peroxidised sections are discussed briefly.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01283035
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