The Nikon MicroscopyU confocal microscopy image gallery was created with a PCM-2000 confocal scanning system interfaced to a Nikon Eclipse E600 upright microscope. Images were recorded in successive z-axis serial sections with C-Imaging Systems software with excitation illumination provided by an argon-ion and/or a helium-neon laser.

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Members of the Kingdom Protista, algae are most common in aquatic habitats, but occur in nearly every environment. They range in size from microscopic to giant kelp that reach 200 feet (60 meters) in length. Algae produce a significant percentage of the Earth's oxygen, are the base of the food chain for nearly all aquatic life, and provide food and industrial products for humans.

Closterium is a desmid, a microscopic green algae that occurs in all types of freshwater habitats. Desmids are typically one-celled, though sometimes filamentous or colonial, and are divided symmetrically into semicells connected at a central point. Closterium is characterized by a sickle shape and sometimes contains gypsum crystals.

Frustulia is one of 16,000 species of diatoms, one of the many groups of organisms that make up the algae. Diatoms are photosynthetic, but have rigid cell walls reinforced with silicon rather than cellulose. They can be found in all aquatic environments and, although they're unicellular, often live in large colonies.

A type of blue-green algae, Oscillatoria is characterized by the gliding movement that it exhibits as it makes its way across the substratum. Species belonging to this genus can be found in hot springs, freshwater, marine, estuarine, and sulfur environments. The Red Sea gets its name from occasional blooms of a reddish species of Oscillatoria.