Biological clock. Conceptual image of a resting boy lying below a tree seen through a watch face, representing the biological clock. Processes such as

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Biological clock. Conceptual image of a resting boy lying below a tree seen through a watch face, representing the biological clock. Processes such as wakefulness and tiredness are based on a daily or circadian (24 hour) cycle regulated by hormones such as melatonin and cortisol.

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Size: 3559px × 2617px
Photo credit: © OSCAR BURRIEL/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: aquatic, biological, biology, botanical, botany, contrast, dic, differential, dinophyta, dinophyte, flora, interference, light, marine, micrograph, microorganism, nature, noctiluca, phosphorescence, protist, protists, sea, single-celled, sparkle, unicellular