Bacillariophyta

  • H. D. Kumar
  • H. N. Singh
Chapter

Abstract

The Bacillariophyta, popularly called diatoms, comprise a homogeneous assemblage of unicellular and colonial forms that differ generally from other algae in possessing highly sculptured and symmetrically ornamented cell walls. The main characters that collectively differentiate the Bacillariophyta from other phyla are: (1) the diploid nature of vegetative cells; (2) the presence of chlorophyll-c together with fucoxanthin, diatoxanthin and diadinoxanthin in chromatophores, the usual brown colouration being due to the preponderance of carotenoid pigments over chlorophylls; (3) the silicified nature of cell walls which consist of two highly perforated overlapping pieces sometimes bearing structures like spines and bristles; (4) the storage of oil and chrysolaminarin and not starch in food reserves; and (5) the reduction in size of cells occurring during vegetative multiplication compensated by the production of spores known as auxospores.

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Selected References

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Copyright information

© Affiliated East-West Press Private Limited 1979

Authors and Affiliations

  • H. D. Kumar
    • 1
  • H. N. Singh
    • 1
  1. 1.VaranasiIndia

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