Nervous System
In the nervous system of sea urchins the spines, podia, and pedicellariae all act as sensors. A circular nerve ring encircles the esophagus, and radial nerves extend inside of the test parallel to the lateral canals of the water vascular system. Sensory neurons in the epidermis can detect touch, chemicals, and light, and are usually associated with pedicellariae or spines.
Read more about this topic: Strongylocentrotus Droebachiensis, Anatomy, Internal Anatomy
Famous quotes containing the words nervous system, nervous and/or system:
“A car can massage organs which no masseur can reach. It is the one remedy for the disorders of the great sympathetic nervous system.”
—Jean Cocteau (1889–1963)
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—Lawrence Kutner (20th century)
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—Doris Lessing (b. 1919)