How do bacteria that use a flagellum for motion direct their

How do bacteria that use a flagellum for motion direct their movement?

Solution

Answer:

Single direction: When the flagellum rotates clockwise, the filament forms a long pitch supercoil, allowing several flagella on a single cell to form a large bundle, which propels the bacterium along a straight line in a single direction.

Random motion: When rotated in the opposite direction, flafellar filament forms a shorter pitch supercoil; this causes the flagellar bundle to disassemble, and the independent motion of several flagella on the cell cause it to tumble randomly.