There is a nerve ring round the pharynx ( throat ) and a ganglion that serves as a brain to one side of this.
12.
The nervous system consists of a ventral nerve cord, with one ganglion in each segment, and an anterior nerve ring surrounding the pharynx.
13.
The brain of a gastropod consists of three pairs of ganglia, all located close to the oesophagus and forming a nerve ring around it.
14.
The " ear " of the nautilus consists of structures called " otocysts " located immediately behind the pedal ganglia near the nerve ring.
15.
Notably, they possess a nerve ring around the base of the bell that coordinates their pulsing movements, a feature found elsewhere only in the crown jellyfish.
16.
The pleural ganglion is located posterior to the cerebral ganglion and connected to the latter and the pedal ganglion by short connectives forming the pre-pharyngeal nerve ring.
17.
On the other hand, sea stars, which are echinoderms, have a nerve net in each arm, connected by a central radial nerve ring at the center.
18.
At the anterior end of the animal, the nerves branch from a dense, circular nerve ( nerve ring ) round surrounding the pharynx, and serving as the brain.
19.
The nerve ring, also called a "'nerve collar "', creates a complete and closed loop around the food-entry parts of the animal's anatomy.
20.
The nervous system consists of a nerve ring around the pharynx and a prominent cord running the length of the body with organs, but there are sensory nerve endings in the body, especially on the proboscis.
