SUSUMU NISHINAGA / SCIENCE PHOTO LIBRARY SUSUMU NISHINAGA / SCIENCE PHOTO LIBRARY
Kidney glomerulus. Coloured scanning electron micrograph (SEM) of a resin cast of the coil of capillaries (red) that form the core of a glomerulus. Surrounding it are the larger blood vessels (orange) that supply it with blood. Glomeruli are found in the kidneys. Capillaries are the smallest blood vessels. Their permeable walls allow substances carried in the blood to be exchanged with the surrounding tissues. Each kidney has hundreds of glomeruli that filter toxic waste from the blood. The resulting waste fluid drains to the bladder as urine. The cast was made by injecting resin into the blood vessels. The surrounding tissues were then chemically digested.
Model release not required. Property release not required.