Search results
Results from the WOW.Com Content Network
Euglena is a genus of single cell flagellate eukaryotes. It is the best known and most widely studied member of the class Euglenoidea, a diverse group containing some 54 genera and at least 200 species. [1] [2] Species of Euglena are found in fresh water and salt water.
Euglenoids are distinguished mainly by the presence of a type of cell covering called a pellicle. Within its taxon, the pellicle is one of the euglenoids' most diverse morphological features. [ 7 ] The pellicle is composed of proteinaceous strips underneath the cell membrane, supported by dorsal and ventral microtubules .
Euglena sanguinea is a species of the genus Euglena.The red colour is due to the presence of astaxanthin and the cells can be populous enough to colour water red. The pigment is used to protect the chloroplasts from light that is too intense, but as the light levels change the cells can take on a green colour as the red pigment is moved to the centre of the cells.
Amphibians such as frogs have three kinds of star-shaped chromatophore cells in separate layers of their skin. The top layer contains ' xanthophores ' with orange, red, or yellow pigments; the middle layer contains ' iridophores ' with a silvery light-reflecting pigment; while the bottom layer contains ' melanophores ' with dark melanin.
Euglenales consists mostly of freshwater organisms, in contrast to its sister Eutreptiales which is generally marine. Cells have two flagella, but only one is emergent; the other is very short and does not emerge from the cell, so cells appear to have only one flagellum. [3] In comparison, Eutreptiales is characterized by two emergent flagella. [4]
Euglenaceae show the most morphological diversity within the class Euglenophyceae. [3] They are mostly single-celled organisms, except for the genus Colacium.They are free-living or sometimes inhabiting the digestive tracts of animals. [1]
This is supported by one of three sets of microtubules that arise from the flagellar bases; the other two support the dorsal and ventral surfaces of the cell. [ 4 ] Some other euglenozoa feed through absorption, and many euglenids possess chloroplasts , the only eukaryotes outside Diaphoretickes to do so without performing kleptoplasty , [ 5 ...
Euglena gracilis is a freshwater species of single-celled alga in the genus Euglena. It has secondary chloroplasts , and is a mixotroph able to feed by photosynthesis or phagocytosis . It has a highly flexible cell surface, allowing it to change shape from a thin cell up to 100 μm long to a sphere of approximately 20 μm.