amoeba-1 - contractile vacuole the concentration of solutes...

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Amoeba 1 Amoeba Amoeba proteus is a microscopic living organism which consists of a single cell. Like most plant and animal cells, it has cytoplasm, nucleus, cell membrane and a variety of inclusions in the cytoplasm. It is about 0.3 mm across and inhabits the mud at the bottom of fresh water ponds. Although it is just a single cell, it exhibits all the essential functions of any living organism. pseudopodium cytoplasm ectoplasm endoplasm contractile vacuole nucleus food vacuole cell membrane cell membrane ; controls the entry and exit of substances into and out of the cytoplasm cytoplasm ; the living substance in which all the chemical reactions necessary for life are carried out. ectoplasm is a clear gel-like layer enclosing the endoplasm which is more fluid and contains granules and other inclusions. nucleus ; controls most of the reactions taking place in the cell and plays a vital part in cell division.
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Unformatted text preview: contractile vacuole ; the concentration of solutes in the cytoplasm is greater than that in the surrounding fresh water, so water tends to enter the cytoplasm by osmosis* via the partially permeable cell membrane. This excess water collects in the contractile vacuole which swells and discharges its contents to the outside from time to time. Structure of an amoeba pseudopodium ; a protuberance from the surface of the amoeba into which the cytoplasm flows; in this way the amoeba moves about over the mud at the bottom of the pond. ( pseudopodium means ‘false foot’) food vacuole; microscopic organisms are taken into the cytoplasm with a drop of water forming a temporary vacuole; these organisms are then digested. © D.G. Mackean 0.1mm * Osmosis is the movement of water from a weak solution to a stronger solution through a partially permeable membrane. © D.G. Mackean...
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