Related topics: brain · nerve cells · current biology · retina

Stabilizing ligands make nanoclusters brighter

Metal nanoclusters that bear tunable surface ligands could help develop next-generation imaging and photocatalytic approaches, suggests work by KAUST researchers.

NASA gets an eyeful of Typhoon Fengshen

NASA's Terra satellite captured an image of Typhoon Fengshen after its eye opened as Fengshen had strengthened from a tropical storm to a typhoon and developed an eye.

The mysterious 'Tully Monster' fossil just got more mysterious

Every now and again, scientists discover fossils that are so bizarre they defy classification, their body plans unlike any other living animals or plants. Tullimonstrum (also known as the Tully Monster), a 300m-year-old fossil ...

Targeted gene modification in animal pathogenic chlamydia

Researchers at Umeå University (Sweden), in collaboration with researchers at the University of Maryland and Duke University (U.S.), now for the first time successfully performed targeted gene mutation in the zoonotic pathogen ...

Drought-stressed forest fueled Amazon fires

A new satellite-based map of a section of the Amazon Basin reveals that at least some of the massive fires burning there this past summer were concentrated in water-stressed areas of the rainforest. The stressed plants released ...

What was the first color in the universe?

The universe bathes in a sea of light, from the blue-white flickering of young stars to the deep red glow of hydrogen clouds. Beyond the colors seen by human eyes, there are flashes of X-rays and gamma rays, powerful bursts ...

A timekeeper for siesta

Circadian clocks must be flexible and they must be able to adapt to varying environmental conditions. Otherwise, it would be impossible for living beings to change their patterns of activity when the days get shorter again ...

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Eye

Eyes are organs that detect light, and send signals along the optic nerve to the visual and other areas of the brain[citation needed]. Complex optical systems with resolving power have come in ten fundamentally different forms, and 96% of animal species possess a complex optical system. Image-resolving eyes are present in cnidaria, molluscs, chordates, annelids and arthropods.

The simplest "eyes", such as those in unicellular organisms, do nothing but detect whether the surroundings are light or dark, which is sufficient for the entrainment of circadian rhythms. From more complex eyes, retinal photosensitive ganglion cells send signals along the retinohypothalamic tract to the suprachiasmatic nuclei to effect circadian adjustment.

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