A Diatom is under the phylum of Chrysophyta with the following characteristics:
1) Unicellular but often colonial
2) manufactures the carbohydrate chrysolaminarin
3) has unique double -shells of opaline silica
4) contains chlorophylls a and c
They are abundant in sea and fresh water where they serve as producers.
Diatoms are protists that have glass walls. Just like plants, they carry out cytokinesis. They are photosynthesizers with hard shells of silica. An example of a Diatom is Diatoma.
Diatoms are divided into two major groups, one with radial symmetry and the other with bilateral symmetry.