Iris. Computer-enhanced image of a blue human iris. The iris is a ring of muscle fibres. It contracts and relaxes to alter the amount of light enterin

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Iris. Computer-enhanced image of a blue human iris. The iris is a ring of muscle fibres. It contracts and relaxes to alter the amount of light entering the eye through the pupil (black).

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Size: 3723px × 3886px
Photo credit: © DAVID PARKER/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: ball, blue, computer-enhanced, eye, eyeball, eyeballs, false-colour, false-coloured, fibres, globe, human, iris, muscle, ophthalmics, ophthalmology, opthalmics, organ, physiological, physiology, pupil, sense, sensory, sight, single, sphere, spherical, vision