Final answer:
A diagram that shows what the inside of something looks like is called a model. Models are used to represent the interior of cells and the arrangement of atoms in compounds.
Step-by-step explanation:
A diagram that shows what the inside of something looks like is called a model. In the context of living things, such as cells, an artist's representation of the interior of a cell is a model that helps us visualize its crowded and busy space, containing cytoplasm, dissolved substances, and many structures.
Models are also used in other areas, such as chemistry, where diagrams of compounds help us to see the arrangement of atoms and the shape of the compound.