pineal eye
Quick Summary
The term "pineal eye" refers to a photoreceptive structure found in some nonmammalian vertebrates. It is also known as the parietal eye and is essentially a pineal gland with the ability to detect light. In certain reptiles, this structure can be eyelike, complete with a lens and retina. While the pineal gland in humans primarily functions as an endocrine gland secreting melatonin to regulate circadian rhythms, in some lower vertebrates, it retains a more developed, light-sensing capability.1234
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crustaceanThe nervous systemSingle median eyes are also found in crustaceans, particularly in the nauplius larvae. Only three or four simple units are usually found in the nauplius eye, which is innervated by a median nerve from the forebrain. The median eye also may persist through to the adult…
Read MoreSingle median eyes are also found in crustaceans, particularly in the nauplius larvae. Only three or four simple units are usually found in the nauplius eye, which is innervated by a median nerve from the forebrain. The median eye also may persist through to the adult…
Read More- cirripedeThe nervous system
The nauplius median eye is generally retained in the adult as a photoreceptor. In sessile barnacles the bilateral parts of the median eye separate and migrate laterally to thin places under the anterior pair of opercular plates, where they function better in the shadow reflex. This reflex…
Read MoreThe nauplius median eye is generally retained in the adult as a photoreceptor. In sessile barnacles the bilateral parts of the median eye separate and migrate laterally to thin places under the anterior pair of opercular plates, where they function better in the shadow reflex. This reflex…
Read More