A bacterial appendage protrudes outward from the surface of the microorganism. Some are highly anchored to the surface, whereas others, like the glycocalyx, are loosely associated with the surface.

The entire surface of a bacterium can be covered with glycocalyx (also known as the slime layer). The layer is made of chains of sugar. Protein can also be present. The exact chemical nature of a glycocalyx varies from one species of bacteria to another. A glycocalyx is easily identified in light microscopy by the application of India ink. The ink does not penetrate the glycocalyx, which then appears as a halo around each bacteria.

A glycocalyx has a number of functions. It aids a bacterium in attaching to a surface. Surface contact triggers the production of a great deal of glycocalyx. The bacteria on the surface can become buried. This phenomenon has been well documented for...