Aorta (cross section)
Note thin intima (top) in a young aorta. Elastic tissue in media has been darkly stained. The internal and external elastic
membranes are not apparent on light microscopy. The media is composed of concentric elastic sheets with interspersed ground substance, smooth muscle cells, and collagen. Note lamellar arrangement of elastic fibers in high magnification photo (inset).
1 minute clinical correlation