Diatoms have cell walls called frustules that contain opaline silica and fine pores. The tiny pores in the frustules make them a useful filtering material for a wide range of industrial products, including beer and jet fuel.
Water Flea with eggs - Daphnia pulex - This most common species of water flea belongs to the family Daphiniidae. It has a cosmopolitan distribution in a wide range of aquatic habitats, although it is most closely associated with small, shaded pools and la
Coloured scanning electron micrograph (SEM) of a passion flower (Passiflora caerulea) pollen grain. Pollen grains are the male gametes (sex cells) of a plant. Magnification: when printed 10 centimetres wide.