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

Novel mechanism of inheritance detected

Non-Mendelian, oligogenic inheritance could be an unrecognized and important element for occurrence of hereditary retinal degenerations (HRDs, comprising retinitis pigmentosa) which are caused by ultra-rare mutations and ...

Partial lunar eclipse to grace U.K. evening sky

Tuesday, 16 July, will see a partial eclipse of the moon, visible in the U.K. after sunset. The eclipse, 50 years to the day after the launch of Apollo 11, will also be seen across a large part of Asia, the whole of Africa, ...

Study: Lethal plastic trash now common in Greece's whales

A study of whales and dolphins that have washed up dead in Greece over a 20-year period has found alarmingly high levels of plastic trash—mostly bags—in the animals' stomachs, which can condemn them to a slow and painful ...

Mapping the ocean's unseen heroes, one microbe at a time

The picture of how climate change is impacting our ocean is often told via its larger inhabitants: scrawny polar bears, bleached coral, dwindling catch in fishing nets. But just as importantly, microscopic marine organisms ...

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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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