How Do Pili And Flagella Allow Bacterial Cells To Survive As Unicellular Organisms?
Pili are small projections on the outer side of a bacterial wall. Flagella are longer and are more like a bacterium’s tail. Flagella help to make a bacterium motile. That means that bacteria use flagella to move. Some pili also help bacteria to move. This is known as twitching motility. These are known as the IV pili. However, more commonly, pili are used during bacterial conjugation. A pili attaches to another bacterium and helps to draw it in to form a mating bridge. This is like a pore in the bacterial wall. The bacterium with the pili can thus transfer its genetic material into the other bacterium. This is advantageous as this lends genetic variation to bacteria through which helpful traits that aid survival of bacteria are transferred between bacteria. The movement allows bacteria to respond to stimuli like heat and chemicals which they need to survive. This is known as chemotaxis for response to chemicals. The pili also help to ensure genetic diversity in bacteria that helps them
