* Structure: Flagella are long, whip-like appendages made of protein. They can be arranged in various ways on the bacterial cell, like single flagella at one end (monotrichous), multiple flagella at one end (lophotrichous), flagella all around (peritrichous), or flagella at both ends (amphitrichous).
* Rotation: Flagella are powered by a motor embedded in the bacterial cell membrane. This motor rotates the flagellum, creating a propulsive force.
* Movement: The rotation of the flagellum pushes the bacterium forward or backward depending on the direction of rotation.
* Tumbling and Running: Bacteria use flagella to navigate their environment. They switch between two modes of movement:
* Running: When the flagella rotate in the same direction, they form a bundle and propel the bacterium forward in a straight line.
* Tumbling: When the flagella rotate in opposite directions, the bundle breaks apart and the bacterium tumbles randomly. This helps the bacterium change direction and explore new areas.
* Chemotaxis: Bacteria can use flagella to move towards favorable environments (like food sources) and away from unfavorable environments (like toxins) through a process called chemotaxis. They sense chemical gradients in their environment and adjust their flagellar rotation to move accordingly.
In essence, flagella act like tiny motors that propel bacteria through their environment, allowing them to find food, avoid danger, and navigate their surroundings.
