Skip to content

Sporopollenin vs. biogenic silica

Definition

Pollen and spore walls are made of sporopollenin (a highly resistant biopolymer). Diatom frustules are made of biogenic opaline silica (SiO2·nH2O), a different chemistry entirely, but equally resistant to biological degradation and a key reason frustules persist in forensic samples.

Related terms

Assemblage
The full community of diatom taxa present in a sample. The relative frequencies and absolute counts of species in an assemblage reflect...
Epitheca and hypotheca
The two halves of the frustule. The epitheca (larger) fits over the hypotheca (smaller) like a lid over a box. During cell...
Frustule
The silica cell wall of a diatom, composed of two overlapping valves (epitheca and hypotheca). Frustules are taxonomically distinctive, chemically resistant to...
Raphe
A longitudinal slit or canal in the valve of certain pennate diatoms that allows cytoplasmic streaming and active gliding movement across surfaces....
Valve and girdle band
The valve is the flat face of each frustule half, carrying the species-specific pore patterns used for identification. The girdle band is...

Explained in

  • Diatom Biology and TaxonomyPollen and spore walls are made of sporopollenin (a highly resistant biopolymer). Diatom frustules are made of biogenic opaline silica (SiO2·nH2O), a different...

Your journey to becoming a forensic professional starts here.

Practice with mock tests, learn from structured notes, and get your questions answered by a global forensic community, all in one place.