Both systems are for messaging. A telephone, of the traditional type, resembles the nervous system with its need for wires (the long extensions, axons of nerve cells or neurons)
whereas the endocrine system, sending chemical messages, is more akin to the post.
The chapter suggested modelling neurons using clay. We used playdough as it is cheap to make and easy to manipulate.
The role of neurotransmitters carrying messages between an axon terminal of one neuron and the dendrites of the next was more easily understood when modelled. Again the dendrite is green, the axon terminal is red. The neurotransmitters are in cream.
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