EVERYDAY SCIENCE

Detailed explanation-1: -The rotation of the filament allows bacteria to move around in their environment. The motor embedded in the bacterial cell membrane rotates-just as a car motor spins beneath the hood of the vehicle-to drive the movement of the filament outside.

Detailed explanation-2: -A bacterium will move forward, called a “run, ” when there is a CCW rotation, and reorient randomly, called a “tumble, ” when there is a CW rotation.

Detailed explanation-3: -Some bacteria have a single, tail-like flagellum or a small cluster of flagella, which rotate in coordinated fashion, much like the propeller on a boat engine, to push the organism forward. The hook: Many bacteria also use appendages called pilli to move along a surface.

Detailed explanation-4: -Gliding motility is the ability of certain rod-shaped bacteria to translocate on surfaces without the aid of external appendages such as flagella, cilia, or pili.