Peranema (Protozoan) Videos

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Peranema, a close relative of Euglena, is a colorless euglenoid. Although euglena have chloroplasts that enable them to produce their own food, peranema have to consume other organisms to survive. A prominent feeding apparatus, composed of two rods, is located at the flagellated (anterior) end of the cell. Peranema sometimes hunt in "packs" and rip away at prey cells, tearing holes in them and sucking out cell contents.

Like other euglenoids, these organisms are actually biflagellate (having two flagella), but only one is easily viewed through the microscope. Beating often occurs only at the tip of the visible flagellum. The second flagellum is thinner, shorter, and difficult to see under the microscope. In species with two obvious flagella, the two flagella are often quite dissimilar both in terms of flagellar structure and function.

The euglenoid flagellates are an ancient eukaryotic lineage and, although typically regarded as members of the Protista, they are something of a taxonomic enigma. For many years, they were classified as algae because some genera (such as Euglena) have chloroplasts. Most euglenoid genera, however, are colorless with no indication that they ever had chloroplasts.

These flagellates can move in a number of ways including basic swimming motion, gliding along a substrate, or changing their body shape in a process known as euglenoid metaboly. Euglenoids are found in both freshwater and marine environments, as well as in soil. A few species live as parasites. Most are free-living unicellular organisms. Only one colonial genus is known to exist.


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