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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Polysiphonia are plant-like organisms that are predominantly found in marine environments and are more commonly known as red algae. Although a few species may be found in freshwater, red algae are typically attached to rocks or other plants in tropical and subtropical deep waters or washed along shorelines. These algae manifest many shapes and close observation reveals filaments, branches, feathers, or sheet-like structures (the scientific name for red algae is derived from Greek words meaning "many pipes"). Red algae are hardy and even tiny fragments are able to survive winter cold or harsh environments by remaining dormant until more favorable conditions encourage them to grow. The reproductive cells of red algae are not equipped to move on their own and fertilization occurs only when male spermatium are carried by water currents to a receptacle on the female reproductive organ.

These algae derive their reddish-brown to reddish-black coloring from a pigment protein referred to as phycobilin, which blankets the green color that is normally reflected by chlorophyll-containing cells. One of the most common varieties forms a branch-like structure that consists of a line of elongated cells that display a segmented appearance and often develop secondary branching that radiates from the algae body. Polysiphonia retains the red coloring as well as a gelatinous nature even when heating and is considered an important food plant that is prized as a gelatin substitute in puddings, ice cream, and toothpaste.