1. Structure and Function: Cells have different shapes and sizes, and these differences reflect their specialized functions. For example, nerve cells have long, thin extensions to transmit signals, while muscle cells are elongated and contract to generate movement.

2. Genetic Makeup: Even within a single organism, cells can have different genetic makeup. This can be due to mutations or the process of differentiation, where cells specialize and express different sets of genes. For example, a muscle cell will have different active genes compared to a skin cell.

3. Location: Cells are often found in specific locations within an organism, reflecting their function and interactions with neighboring cells. For example, epithelial cells line the surfaces of organs, while red blood cells circulate in the bloodstream.