Inner ear hair cells. Coloured scanning electron micrograph (SEM) of sensory hair cells from the inner ear. These cells are surrounded by a fluid called endolymph. As sound enters the ear it causes waves to form in the endolymph, which in turn cause the hairs to move. The movement is converted to an electrical signal that is passed on to the brain. Each crescent-shaped arrangement of hairs lies atop a single cell.
Brain tumour. Coloured scanning electron micrograph (SEM) of a glioma, a type of tumour that arises from glial cells of the central nervous system. The most common site for gliomas is the brain. They can be either low or high-grade, with the latter having the worse prognosis. Magnification: x8000 when printed at 10 centimetres wide. Credit: STEVE GSCHMEISSNER
Ruptured venule. Coloured scanning electron micrograph (SEM) showing stacks (rouleaux) of red blood cells exposed inside a torn venule. A venule is a very small blood vessel in the microcirculation that allows deoxygenated blood to return from the capillary beds to the larger blood vessels (veins). Red blood cells are the most abundant cell in the blood. They have no nucleus and are about 7 micrometers across. Magnification: x2300 when printed at 10 centimetres wide.
Scanning electron micrograph of part of a thale cress flower, showing the male and female reproductive organs. The female part of the flower, the pistil (the blue feathery structure on an olive green stalk), is at the centre of the image and contains egg cells (ovules) housed in an ovary. It is surrounded by the male parts, the stamens, which have their anthers coloured light green and their filaments brown. Photography by Stefan Eberhard
Retina. Coloured scanning electron micrograph (SEM) of rods (yellow) and cones (green) in the retina of the eye. The outer nuclear layer is purple. Magnification x1800 when printed at 10 centimetres wide. [F0010041] Incredible!!
Nerve bundle. 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.
Fat tissue. Coloured scanning electron micrograph (SEM) of a sample of fat tissue, showing fat cells (adipocytes, blue) surrounded by fine strands of supportive connective tissue. Adipocytes are among the largest cells in the human body, each cell being 100 to 120 microns in diameter. Almost the entire volume of each fat cell consists of a single lipid (fat or oil) droplet. Adipose tissue forms an insulating layer under the skin, storing energy in the form of fat, which is obtained from…
Scanning electron micrograph (SEM) of cancellous (spongy) bone of the human shin. Bone tissue is either compact or cancellous. Compact bone usually makes up the exterior of the bone, while cancellous bone is found in the interior. Cancellous bone is characterised by a honeycomb arrangement of trabeculae. These structures help to provide support and strength. The spaces within this tissue normally contain bone marrow, a blood forming substance. Credit: SCIENCE SOURCE/SCIENCE PHOTO LIBRARY