Nervous system
... Glia(e) are special cells of the nervous system which aid the neurons by providing them with nutrients, insulating them and removing cellular debris when the cell dies. ... The element of the neuro system which activates the next neuron is called neurotransmitter. ... It is very important for our nervous system to have inhibition because without it, sleep and co-ordination would be impossible. ... Endorphins are the chemical substances that are found in the nervous system. ... Endorphins are chemical substances in the nervous system that are similar in structure and action to opiates.