Amebas are tiny, one celled organisms in the Protista kingdom that usually can only be seen under a microscope. Amebas vary in size from about 1/100 inch (0.25 millimeter) to 1/10 inch (2.5 millimeters) across. Amebas can live in water, moist soil or in the bodies of animals and human beings. The single cell that makes up an ameba is a shapeless mass of protoplasm, the living, jelly like material found in the cells of all living things.
A thin, selectively permeable plasma membrane surrounds the protoplasm to hold the ameba together and allow water, gases, food, wastes, and other substances to pass in and out of the cell. The protoplasm extends and recoils in a pseudo pod , allowing the ameba to move about its environment. Cells that move in this way are called ameboid cells.
Amebas eat tiny living organisms and particles of dead and decaying matter. They engulf their food by slowly wrapping pseudo pods around a food particle. In this way, the food gets inside the cell. The section of the cell that contains the food is called a food vacuole. It floats in the protoplasm until the food is digested. All undigested food is forced out of the cell through the plasma membrane. Amebas in fresh water must remain hypertonic to their environment in order to survive, thus they contain contractile vacuoles to export excess water that enters the cell. Amebas reproduce by fission when they reach a certain size, and each new daughter cell is able to grow, feed, and divide. Most amebas are harmless to people, but some may cause diseases such amebic dysentery caused by infection in the large intestine.
I like them yes I do....
2006-08-24 08:31:13
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answer #1
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answered by Lucid_dreams 4
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Shure, i dont dis like them.
2006-08-24 08:31:31
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answer #2
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answered by Anonymous
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okay what kinda question is that.. its not like we see or talk to them or anything
2006-08-24 08:31:03
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answer #3
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answered by Anonymous
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