What is the nature of cell-walls in diatoms?

 Diatoms are unicellular algae that have a unique cell wall made of silica, a chemical compound that is hard and brittle. The cell wall of a diatom is called a frustule, and it consists of two overlapping valves that fit together like a pillbox. The frustule is perforated by small pores that allow for the exchange of gases and nutrients.

The frustule is composed of two layers, an outer layer called the epitheca and an inner layer called the hypotheca. The two layers are fused together at the edges to form a tight seal that helps to maintain the structural integrity of the cell.

The silica that makes up the frustule is arranged in intricate patterns that are characteristic of each species of diatom. These patterns can be seen under a microscope and are used to identify different species of diatoms.

The unique structure of the diatom frustule makes it an important component of aquatic ecosystems, where it serves as a major source of food for many marine organisms. Additionally, the intricate patterns of the frustule have inspired artists and designers for centuries.



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