Coloured scanning electron micrograph (SEM) of neuromuscular junctions. These are junctions between a nerve cell, or neuron (beige and yellow), and a muscle (red), where a nerve passes a signal to the muscle telling it to contract. Nuclei (round, orange) are also seen. The picture was created as part of a cooperation with Quintessenz Publishing. Magnification: x1,500 when printed at 15cm wide.