Lung alveoli and red blood cells. Coloured transmission electron micrograph (TEM) of a section through lung alveoli (yellow) and red blood cells (red). Alveoli are the site of gaseous exchange in the lungs, where oxygen is taken up by the red blood cells and carbon dioxide released for exhalation out of the body. Red blood cells have a biconcave surface, which produces a double-lobed shape when seen in vertical cross-section. Magnification: x2400 when printed at 10 centimetres wide.
Model release not required. Property release not required.