DR GOPAL MURTI / SCIENCE PHOTO LIBRARY DR GOPAL MURTI / SCIENCE PHOTO LIBRARY
Heart muscle. Coloured transmission electron micrograph (TEM) of a longitudinal section through healthy heart (cardiac) muscle. Large mitochondria (green) lie between the muscle fibres (red). The thick transverse bands on the fibres are Z lines, regions with a more dense arrangement of actin, one of the two types of muscle filament. In order to beat, the heart produces regular electrical impulses causing the muscle filaments to slide over one another and contract the cardiac muscle. The high concentration of mitochondria reflects the large respirational demands of the heart. Magnification: x5000 at 35mm size.
Model release not required. Property release not required.