with a flagellum
It is a single-celled alga; it also has a peephole near the flagellum.
Here is a miracle, like algae, but it moves and even has an eye! At school I was amazed))
And yet, it causes water to bloom)
Euglena is a green amazing microorganism, on the one hand it is an animal, and on the other hand it can receive energy through photosynthesis and therefore is a plant (alga). And she moves with flagellum located at one end of it. Movement occurs due to the rotational movements of the flagellum.
Movement euglena green
The movement of euglena green is carried out with the help of a long and thin protoplasmic process - flagellum, located on the front end of the body eugleins. Thanks to him, euglena green moves. The flagellum produces a spiral motion, as if screwing into the water. Its action can be compared with the action of the propeller of a motor boat or steamer. Such a movement is more perfect than movement with the help of paws. Estroglen moves much faster than the ciliate shoe.
Food euglena green
Considering Euglene green under a microscope, one can see in the protoplasm of its body a large number of small green oval bodies. These are chromatophores that contain chlorophyll. This evuglena resembles green plants. Like them, with the help of chlorophyll, it can absorb carbon from carbon dioxide, forming in its body organic matter from inorganic. But along with such typically vegetative nutrition, euglena green can also feed on ready-made organic substances that are always in a dissolved state in heavily overgrown or polluted water in water. It digests these substances with the help of digestive vacuoles, as does the ameba ordinary. Therefore, euglena green can eat both as a plant and as an animal.
The nature of its food depends on the presence or absence of light in the reservoirs in which this animal lives. In the afternoon, in the presence of light, euglena green feeds on like a plant. In the absence of light, the way it feeds changes: like animals, euglena feeds on ready-made organic substances. With this diet, the chlorophyll present in the chromatophores disappears and euglena loses its green color. If placed in a darkness, euglena becomes discolored and begins to feed like an animal.
The dual way of eating eugle green is an extremely interesting phenomenon. It indicates the common origin of plants and animals. Comparing higher multicellular animals with higher plants, we can easily distinguish them. We will not find such an obvious difference if we compare lower single-celled animals (for example, Euglene green) and unicellular plants.
The structure is euglena green
Outside the cell is covered with a thin elastic layer of the cytoplasm - pellicle, playing the role of the shell. From the front end of the body, one bundle departs from the euglena, due to the rotation of which it moves forward. At the base of the flagellum there is always a special thickening, against which the eye spot lies.
Euglena got its name for the color that green chromatophores impart to the cell.
They have an oval shape and are usually located in a star-shaped cell. Photosynthesis occurs in chromatophores. Formed in the light of carbohydrates are deposited in the cell in the form of colorless grains. Sometimes there are so many of them that they close the chromatophores, and the euglena becomes whitish. In the dark, the processes of photosynthesis cease, and euglena begins to digest the accumulated grains of carbohydrates and turns green again.
In nature, eugleins usually live in polluted waters with a large amount of dissolved organic matter, so they usually combine both food tops - photosynthesis, typical of plants, and nutrition, typical of animals. Thus, euglena, on the one hand, is a plant, on the other hand, an animal. Such a “mixed” structure of it still causes controversy among scientists: botanists attribute the euglen to a special type of plant, while zoologists distinguish them into a detachment of the subtype of flagellates.
Some members of the Euglene order (relatives of Euglena Green) are not at all capable of photosynthesis and feed like animals, for example, astasia (Astasia). Such animals can develop even complex mouthpieces, with which they absorb the smallest food particles.
How to move green euglena
Not all evglens move only with the help of flagella. In some of them, the movement is provided by wavy contractions of the body. The mechanism underlying this type of movement is not yet completely clear. Under the cell membrane of these protozoa, helically located protein bands that are capable of contraction are found. It is assumed that there is a connection between the cell organelles that produce energy and these contractile protein threads. This type of movement may also involve mucus, which is secreted by the cell through a special excretory channel.
Reproduction euglen green
Often in nature, under certain favorable conditions, mass reproduction of euglen occurs. Then the water in the pond or river creek, which yesterday was still transparent, becomes dull green or brownish. In a drop of this water under a microscope, one can see the mass of euglen.
The closest relatives of Euglena green are Euglena sanguined and Euglena snowy (E. nivalis). With the mass reproduction of these creatures can happen amazing things. Even Aristotle in the IV century BC. described the emergence of "bloody" snow. C. Darwin observed this phenomenon while traveling on the ship "Beagle".
In our country, the "flowering" of snow was repeatedly observed in the Caucasus, the Urals, Kamchatka and on some islands in the Arctic. Everything is explained simply - some flagellates are able to live even on such unsuitable places for living creatures like snow and ice. As a result, during the mass reproduction of flagellates, snow acquires the color that the cytoplasm of these protozoa has. Green, yellow, blue and even black “bloom” of snow is known, but red is more often observed, caused by a large number of propagated eugleins - bloody and snowy.
Euglena food green
In the cytoplasm of euglena green there are more than 20 green oval chloroplasts, giving it a green color (hence the name euglena - green). Chlorophyll is in chloroplasts. It feeds on euglena in the light, like green plants, building its body from organic substances formed in the light through photosynthesis. In the cytoplasm, small grains of reserve nutrient accumulate, similar in composition to starch and consumed during fasting by eugleins.
If you place euglena for a long time in darkness, the chlorophyll in it disappears, it becomes colorless. As a result, photosynthesis is stopped, and euglena begins to assimilate dissolved organic matter formed during the decomposition of various dead organisms.
Euglena green can feed in two different ways: in the light - like green plants, in the dark - like animals, assimilating ready-made organic matter. Such a feature of it, as well as the similarity in the structure of the cells of plants and animals, indicate a relationship between plants and animals.