Euglenas are single celled microorganisms that exist in the class of flagellates that are commonly found in fresh water. As of today there are over 1,000 different species of euglena and many more are waiting to be discovered and named. Several of the species that are named include several species without chloroplasts. Some euglena are said to have both animal and plant features and it is because of this that no one knows how or where to classify those particular species. According to the five kingdom classification system, the euglena has accurately been placed in Phylum Mastigophora family, due to the cell using flagellum as a way of movement.
Euglena is a microorganism that can eat food like that of an animal and can photosynthesize like a plant. When a euglena consumes food like an animal, it surrounds its food and engulfs it, as a plant the euglena utilizes chloroplasts; hence the reason euglena species are green. Euglenas see by a cell that contains an eyespot, or photoreceptive organelle. This eyespot allows the euglena to sense the light and the intensity of the light, telling it to swim in that direction, allowing it to adjust its position to benefit most from the light, and aiding its photosynthesis process. The eyespot also contains photo- sensitive areas at the base of the flagellum that only allow certain light to hit it, light used for growth. When the eyespot is observed under a microscope, it appears as a dark orange- reddish spot, the color is produced by pigments that are contained in pigment bodies called, pigment granules. The eyespot of the euglena contains about 200 different proteins, all of which aid the euglenas ability to sense and see.
Euglena can survive in fresh and salt water. In areas of low moisture the euglena produces a protective wall around its body and then lies dormant until more favorable conditions arise. The euglena can survive very well in dark waters, by storing a carbohydrate, known as paramylon, within its body. This particular cell has been found to reproduce asexually, with no evidence of sexual reproduction. Studies have shown acidity and alkalinity can affect reproduction and the life span of the euglena differs widely between different species. The Euglena also lack cells walls, but have pellicle instead. Pellicle is a thin layer supporting the cell membrane, which protects them and allows them to retain their shape.
http://www.biologycorner.com/worksheets/euglenacolor.htm
http://www.fcps.edu/islandcreekes/ecology/euglena.htm
