Page 24 - The Microworld Miracle

In addition to their cell membrane, bacteria also possess micro-
scopic hairs known as cilia and an organelle called the flagellum,
both of which lets them move. When these microscopic hairs are ex-
amined close-up, we encounter a real miracle. The flagellum—
which has a different molecular structure from that comprising the
bacterium's sheath and cilia—is the only organelle capable of truly
moving backwards in the whole living world. The cilia hairs set up

a wave motion towards from the root to the end, and thanks to the
engine in its roots the fibers of the flagellum arranged in spiral (hel-

Axis
of ro-
tation

Flagellum

THE MICROWORLD MIRACLE External membrane

Floor
Cell membrane
Shaft
Rotating filament
Plasma membrane

Bacteria are equipped with various means of locomotion.
Among these are the micro-hairs known as cilia. Another is the
flagellum, the only structure in the living world able to literally
move backwards.
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