there are two main kinds of cells: prokaryotic and eukaryotic. prokaryotic cells have only a few parts. their dna is the shape of a circle, inside the cytoplasm, and they have no membranes inside the cell. eukaryotic cells are more complex, and they have a cell nucleus. the dna is inside the nucleus, and a membrane is around the nucleus. eukaryotic cells also have other parts, called organelles. some of these other organelles also have membranes.