This is the beginning of the series of cells defined by their mitochondrial membranes. It assumes that by the isolating and staining and processing steps required to visualize cells under the microscope, all have been stripped away, leaving behind only the essence of the cell machinery that produces the energy to subsist: the network of mitochondrial membranes (in silver like electrons racing away), over a dark cloak that covers everything else. The essence of the energy of the cell.