Even with an ordinary (microscope), you must look closely to see bacteria. Using a (magnification) of 100 times, one finds that bacteria are barely visible as tiny (rods or dots). One cannot make out anything of their (structure). Using special stains, one can see that some bacteria have attached to them wavy- looking "hairs" called (flagella). Others have only one flagellum. The flagella (rotate), pushing the bacteria through the water. Many bacteria lack flagella and cannot move about by their own power, while others can glide along over (surfaces) by some little- understood mechanism.
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