Chondrichthyes
Chondrichthyes nervous system is composed of a small brain, 8-10 pairs of cranial nerves, and a spinal chord with spinal nerves. They have several sensory organs which provide information to be processed. Ampullae of Lorenzini are a network of small jelly filled pores called electroreceptors which help the fish sense electric fields in water. This aids in finding prey, navigation, and sensing temperature. The Lateral line system has modified epithelial cells located externally which sense motion, vibration, and pressure in the water around them. Most subspecies have large well-developed eyes. Also, they have very powerful nostrils and olfactory organs. Their inner ears consist of 3 large semicircular canals which aid in balance and orientation. Their sound detecting apparatus has limited range and is typically more powerful at lower frequencies. Some subspecies have electric organs which can be used for defense and predation. They have relatively simple brains with the forebrain not greatly enlarged. The structure and formation of myelin in their nervous systems are nearly identical to that of tetrapods, which has led evolutionary biologists to believe that Chondrichthyes were a cornerstone group in the evolutionary timeline of myelin development.
Jellyfish as food
Jellyfish salad, a popular dish in some areas of Asia, may be prepared using cold marinated jellyfish that is thinly sliced. Some Asian airlines serve jellyfish salad as a part of their airline meal fare. Jellyfish sushi is consumed in Japan. In Thailand, a crunchy style of noodle is produced using jellyfish. The Japanese company Tango Jersey Dairy produces a vanilla and jellyfish ice cream. The ice cream is prepared using Nomura's jellyfish ("Echizen kurage" in Japanese), and involves soaking cubes of the diced jellyfish in milk. It has been described as "slightly chewy." Another reaction to the 2009 Japanese Nomura's jellyfish bloom, students in Obama, Fukui designed a Nomura Jellyfish powder to be used to make caramel sweets as part of a NASA-designed food safety management system established in the school.