Final answer:
The mosaic part of the fluid mosaic model indicates the diverse, tile-like arrangement of phospholipids, proteins, and other molecules in the plasma membrane that are able to move fluidly within the membrane's plane.
Step-by-step explanation:
The mosaic part of the fluid mosaic model refers to the structure of the plasma membrane, which is composed of a variety of components such as phospholipids, cholesterol, proteins, and carbohydrates. These components are arranged in a pattern that resembles a mosaic - similar to multicolored tiles - and are not fixed; instead, they have the ability to move around fluidly within the membrane's plane. This fluidity and mosaic-like arrangement allow the membrane to maintain its integrity while permitting the mobility of its components, facilitating various functions like the activities of enzymes and transport molecules within the membrane.