Cardiac muscle. Coloured scanning electron micrograph (SEM) of cardiac muscle fibrils (blue) from a healthy heart. Mitochondria (purple) supply the mu

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Cardiac muscle. Coloured scanning electron micrograph (SEM) of cardiac muscle fibrils (blue) from a healthy heart. Mitochondria (purple) supply the muscle cells with energy. The muscle fibrils, or myofibrils, are crossed by transverse tubules (vertical lines). These tubules mark the division of the myofibrils into contractile units (sarcomeres). Cardiac muscle is under subconscious control and continuously contracts to pump blood around the body without tiring. Magnification: x5400 when printed 10cm wide.

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Size: 4000px × 2962px
Photo credit: © STEVE GSCHMEISSNER/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

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