Blood clot. Coloured scanning electron micrograph (SEM) of a blood clot from the inner wall of the left ventricle of a human heart. Red blood cells (erythrocytes) are trapped within a fibrin protein mesh (cream). The fibrin mesh is formed in response to chemicals secreted by platelets (pink), fragments of white blood cells. Clots are formed in response to cardiovascular disease or injuries to blood vessels. Connective tissue (orange) is also seen
Axones nerviosos - A cross section of a bundle of nerve fibers. Axons (orange) are wrapped in myelin (purple); an extension of the membrane of glial cells. Myelin has high lipid content, and acts to insulate the axons, causing them to transmit nerve impulses much faster.
Photos of the Amazing and Gruesome World Under a Microscope