Caption

Kidney glomerulus. Coloured scanning electron micrograph (SEM) of podocyte cells (red and orange) on a glomerulus in the kidney. Glomeruli are made up of a tight knot of blood capillaries covered with podocyte cells, whose swollen nuclei and thin extensions are seen here. These tiny filtration units remove toxic waste products from the blood. Filtration occurs through the filtration slits between the interlocking pedicles (the terminal extensions of the podocytes). Filtered fluid then passes into the cavity of the surrounding Bowman's capsule, and drains to the bladder as urine. Magnification: x4,200 at 6x7cm size.