Diatoms are primarily made of silicon dioxide (SiO2), also known as silica, which forms their intricate cell walls. These "glass houses," as they're often called, give diatoms their distinctive and diverse shapes.
Diatom Structure and Composition
The silica cell wall of a diatom, called a frustule, is composed of two overlapping halves, similar to a petri dish and its lid. This unique structure provides protection and support for the diatom.
- Material: Silicon Dioxide (SiO2)
- Structure: Frustule (two overlapping halves)
- Function: Protection and support
Types of Diatoms
Diatoms are broadly classified into two main groups based on their shape:
- Pennate Diatoms: These are elongated, cigar or pen-shaped diatoms.
- Centric Diatoms: These are disk, drum-shaped, or cylindrical diatoms.
Significance of Silica
The silica composition of diatoms is crucial for several reasons:
- Strength: Silica provides structural rigidity to withstand environmental pressures.
- Light Interaction: The silica frustule interacts with light, aiding in photosynthesis.
- Decomposition Resistance: Silica is resistant to decomposition, allowing diatom remains to accumulate in sediments.
Diatomaceous Earth
When diatoms die, their silica frustules accumulate on the ocean floor or in lake beds, forming a sediment known as diatomaceous earth. This material has various industrial applications, including:
- Filtration
- Polishing
- Pest control
In summary, diatoms are fascinating microscopic organisms whose cell walls are primarily composed of silicon dioxide, giving them unique structures and important ecological roles.
