Trilobite is a member of the group of extinct arthropods found as fossils and they can be identified by the three-lobed as well as three segmented forms. These were the marine animals. These were appeared initially in the Cambrian Period. They used to live 542 million years ago so the fossils can be estimated to be aged of 500 above years old. These animals used to dominate in the sea area.
There is three types of neurons occur. Sensory neurons typically have a long denfrite and short axon, and carry messages from sensory repeptprs to the central nervous system. Motor neurons have a long axon and short dendrites and teansmit messages from the central nervous system to the muscles.