GROWTH RATES AND ULTRASTRUCTURE OF SILICEOUS SETAE OF CHAETOCEROS GRACILIS (BACILLARIOPHYCEAE)2

Autor: A. G. Mcinnes, A. S. W. Defreitas, A. Rogerson
Rok vydání: 1986
Předmět:
Zdroj: Journal of Phycology. 22:56-62
ISSN: 1529-8817
0022-3646
DOI: 10.1111/j.1529-8817.1986.tb02515.x
Popis: The growth of setae in post-division Chaeloceros gracilis Schutt was triphasic. Following cell separation there was an initial lag phase of about 30 min after which setae grew linearly at rates ranging from 0.20 to 0.38 μm-min−1. The growth rate was independent of whether diatoms cultured in medium containing 200 μM Si were transferred for experimentation to media containing 10 or 200 μM Si. When developing setae had attained a length of approximately 2 μm, their growth rate slowed as they entered a clearly defined plateau phase. The amount of silicon per unit length of setae was found to be 0.02 pg Si μm−1, and the deposition rate was estimated as 0.005 Pg Si min−1. Transmission electron microscopy revealed an axial structure resembling a microlubule extending the length of each seta and membrane bound polyphosphate bodies postulated to be the energy source for growth and associated biomineralization processes.
Databáze: OpenAIRE