Urethral sphincter. Endoscope image of the internal urethral sphincter. This is the group of muscles that surround the opening from the bladder to the

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Urethral sphincter. Endoscope image of the internal urethral sphincter. This is the group of muscles that surround the opening from the bladder to the urethra, the tube that carries urine out of the body. This is the view from the urethra. The sphincter is made up of smooth (involuntary muscle), which is controlled by the autonomic nervous system rather than being under conscious control. The muscles contract to close the opening and relax to open it.

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Size: 3425px × 2569px
Photo credit: © MR GORDON MUIR/CONSULTANT UROLOGICAL SURGEON/RENAISSANCE HEALTHCARE LTD/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: anatomical, anatomy, biological, biology, bladder, body, circle, circular, diagnosis, diagnostic, endoscope, endoscopy, healthy, human, internal, involuntary, male, man, muscle, muscles, normal, smooth, sphincter, system, urethra, urethral, urinary