Coronary artery. Coloured transmission electron micrograph (TEM) of a crosssection through the wall of a coronary artery. The inside (lumen) of the artery is at upper right. The wall of the artery is made up of an endothelial lining (green), smooth muscle (redbluegreen) and elastic tissue (yellowgreen). Coronary arteries supply the thick muscular wall of the heart with blood. Magnification: 3000x when printed 10 centimetreswide.
