How does Euglena move

Encounters with nature 5, textbook

28 Cell Biology M Workbook Page 8 Characteristics of Life Protozoa are microscopic organisms that, as their name suggests, consist of only one cell. This cell shows all life phenomena such as movement, irritability, metabolism (nutrition, breathing, material transport, material breakdown, material structure, excretion), growth, reproduction and reproduction. Cells are therefore the smallest viable building blocks of living things. They are demonstrated below using the example of the eye animal. Euglena moves by scourge blow. The spindle-shaped body has a sack-shaped depression at its front end, in which two flagella (p. 20) are anchored. One of them protrudes far out of the depression (draft flagella), the other is short and merges with the long one in the flagellum sac. By flapping and rotating the pulling whip, the single-celled body rotates around its longitudinal axis and moves forward in the process. Euglena reacts to light In the area of ​​the flagellum sac is the red colored eye spot due to the inclusion of dyes, which enables a reaction to light. Euglene always turn their body so that the longitudinal axis of their body is in the direction of incidence of light. Euglena has a metabolism. Numerous chloroplasts are stored in the cytoplasm. Photosynthesis takes place in them (p. 42 ff.). However, if there is a lack of light, the ophthalmic animals can also take in dissolved form of food from the environment over the entire surface of the body or solid food particles through the formation of food vacuoles (phagocytosis, p. 20; Fig. 9). Thus, depending on the light conditions, Euglens can eat both autotrophically and heterotrophically. The breakdown of sugar for energy supply, cell respiration (p. 46), takes place in the mitochondria. The oxygen required for this is absorbed from the environment over the entire cell surface. Both water penetrating the cell and metabolic end products that are no longer required are constantly excreted via contractile vesicles. Euglena multiplies through longitudinal division Due to the build-up of endogenous substances, the eye animal increases in body size. Once it has reached a certain size, the cell body divides lengthways (after previous multiplication of the cell organelles, doubling of the DNA and mitosis). Euglena reproduces asexually (asexually). Since there is no new combination of genetic material here, the successor cells have the same genes as the parent cell. Genetically identical offspring are called clones. Plants also perform movements. Do some research and possibly give a presentation about it. Active yourself! 31 Euglens under the light microscope 32 Cell structure by Euglena (scheme) Building blocks of living beings If several cells are in loose contact with one another, one speaks of a cell group (e.g. colony, p. 32). If several cells have the same specialized function, one speaks of a tissue (e.g. muscle tissue, parenchyma, p. 155). Eye animals or euglenes are about 0.05 mm small, single-celled autotrophic, heterotrophic organisms in freshwater that are able to to build energy-rich organic substances (eg sugar) from inorganic substances (e.g. water and carbon dioxide), who are referred to as autotrophic. Green plants are autotrophic. Organisms that feed on organic matter from other living things are called heterotrophic. Non-green plants, fungi, animals and humans have a heterotrophic diet. Contractile vesicles The rhythmic swelling and waning of the cell is used to pump excess water out of the cell (there is a higher substance concentration inside the cell than in the surrounding environment!). short flagellum flagellum sac contractile vesicles eye spot traction flagellum chloroplasts mitochondria For testing purposes only - property of the publisher öbv

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