Low power scanning electron microscope image, showing osteoporotic architecture in the fourth lumbar vertebra of an 89 year old woman (x20). The bone is heavily eroded in places by the action of osteoclasts and consists mainly of thin, fragile struts.
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.
Nerve bundle. Coloured scanning electron micrograph (SEM) of a freeze-fractured section through a bundle of myelinated nerve fibres. Myelin sheaths (yellow) can be seen surrounding the axons (blue). Perineurium (connective tissue, pink) surrounds the nerve bundle while endoneurium divides the individual fibres.