cell membrane- city border
cell wall- city wall
cytoplasm- lawns
endoplasmic reticulum- highway or road system
ribosomes- lumber or brick yard
golgi apparatus- post office
vacuole- warehouses, garbage dumps
chloroplasts- solar energy plants
nuclear envelope- city hall fence with security guards
mitochondria- energy plants
nucleus- city hall
nucleolus- copy machine
lysosomes- waste disposal