Give the salient features and importance of chrysophytes.

Explanation

Chrysophytes includes diatoms and golden algae (desmids). They are found in freshwater as well as in marine water. Most of them are photosynthetic. In diatoms the cell wall form two thin overlapping shells, epitheca over hypotheca which fit together as soap box. The wall are embedded with silica and thus the walls are indestructible. Diatoms leave larger amount of cell wall deposits in their habitat, this accumulation is referred as diatomaceous earth or kieselghur. They reproduce a sexually by Binary fission and sexually by gametes.
Importance :
(i) The diatomaceous soil is used.in polishing, filtration of oils & syrups.
(ii) Diatoms are the chief "producers" in the oceans.