We chose police to represent the cell membrane because the police control the city and who is able to be in the city just as the cell membrane controls what materials are in the cell.

Buildings are the cytoplasm of the city because they fill the city

The city hall represents the nucleus because it contains all the information of the city and acts as the control center just as a nucleus does for the cell

The streets of the city define the shape of it and and anchor buildings as a cytoskeleton does for the cell

Restaurants provide food for the city just as smooth ER provides lipids and vesicles

Mail trucks or any delivery truck deliver things to specific locations just as the rough ER transports proteins to parts of the cell

Factories make products for distribution throughout the city just as ribosomes do with proteins

A post office packages and sorts mail and packages for delivery just as a Golgi apparatus does for proteins to deliver to parts of the cell

The power plant provides energy for the city just like the mitochondria produces power for cell processes

Water tower stores water for later use just as the vacuoles do for the cell

The trash dump is like lysosomes because they contain waste from the city

The city limit is like the cells all because it surrounds the city just like the cell wall does for the cell

The food processing plant produces food as usable energy for people of the city just as chloroplasts make glucose for the cell