Cnidarians - Cnidarians have no brain at all. To replace the central nervous system Cnidarians have nerve nets, which consists of Sensory Neurons. The sensory neurons rely on other stimuli with other signals which make other neurons send different signals. An example of this is the Motor Neuron, which causes muscles to retract. Cilia that is found in Cnidarians neurons detects physical contact. In order for the organism to be able to live these systems of web like neurons are vital because they control movement, coordination and reactions to certain odors.
Jellyfish - Jelly fishes nerve cells are organized into nets and nerve rings. They have no central nervous system and they are brainless.
Maroon Anemone - They have a primitive nervous system, without centralization, coordinates the processes involved in maintaining homeostasis as well as biochemical and physical responses to various stimuli. There are no specialized sense organs.
Northern Cup Coral - Northern Cup Coral like all Cnidarians have no Central nervous system. They share two anatomical features with other Cnidarians: a gastrovascular cavity (simple stomach) that opens only on one end, and a ring of tentacles. The Ring of tentacles help them feel things on the outside.
Jellyfish - Jelly fishes nerve cells are organized into nets and nerve rings. They have no central nervous system and they are brainless.
Maroon Anemone - They have a primitive nervous system, without centralization, coordinates the processes involved in maintaining homeostasis as well as biochemical and physical responses to various stimuli. There are no specialized sense organs.
Northern Cup Coral - Northern Cup Coral like all Cnidarians have no Central nervous system. They share two anatomical features with other Cnidarians: a gastrovascular cavity (simple stomach) that opens only on one end, and a ring of tentacles. The Ring of tentacles help them feel things on the outside.