Diatom (Navicula sp.). Coloured scanning electron micrograph (SEM) of a single diatom. Diatoms may be extremely abundant in both freshwater and marine ecosystems; it is estimated that 20% to 25% of all organic carbon fixation on the planet is carried out by diatoms. This is possible because they contain chlorophyll. Diatoms are thus a major food resource for marine and freshwater microorganisms and animal larvae,and are a major source of atmospheric oxygen. A unique feature of diatom cells is that they are enclosed within a cell wall made of silica (hydrated silicon dioxide) called a frustule. Magnification: x2300 when printed at 10 centimetres wide | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Gschmeissner, Steve |
Taille de l’image : | 4815 px × 3629 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |