A neuron is a cell that will get messages from the brain and send it to other parts of the body to make you move or physically feel something. In a neuron there are the parts of the neuron which i labeled in my photo. The main parts are the cell body, the dendrites, the axon, the node of Ranvier that is in-between the myelin sheath. How a message does through the neuron is the dentaries that send the message, and it goes through the cell body to the axon to send a message. It goes through the node of Ranvier hoping over the myelin sheath which gives it a lot of action potential going through and then goes thought the axon on terminal to give the message. Once the action potential gets to the end of the axon it goes through synapses which send the chemical signal from the axon to another cell. Throughout the action potential there are 3 stages depolarization which is when the messages are going through the membrane letting Na into the membrane. Then repolarization which is when a new channel opens letting K out repolarization cause depolarization. Lastly is the refractory period, it will push the Na in the axon and K out to restart the stages. 

The start of synapses is in the axon terminal bulb with the message will produce neurotransmitters and store it in the synaptic vesicles. The action potential then pushes the synaptic vesicles though presynaptic membrane on the axon bulb into the synaptic gap which is a space between the axon and dentaries. The neurotransmitter then diffuses through the gap and binds to the postsynaptic membrane and receives the message.