Page 180 - The Miracle of Hormones

THE MIRACLE OF HORMONES

Recent research has shown that neurons can contain and release more
than one kind of chemical messengers. In other words, every neuron is
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like a chemical plant that produces the messengers that will be used in
communication.
The neuron that sends the signal is the "transmitter" and the one to
which it is sent the "receiver." The transmitter and receiver neurons meet
at the synapse, a space about 0.00003 of a millimeter. Aparticular elec-
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tric signal activates the messengers on the axon terminal of the transmit-
ting nerve cell. The synaptic endings filled with chemical messengers
combine with the cell membrane and release the molecules inside them
into the synapse cavity. The message carried by the messengers is sent to

The picture shows communication between two neurons. The most important elements
in this communication are messenger molecules known as "neurotransmitters."
neurotransmitter
synaptic vesicles

synaptic cleft receptor
cell body
dendrite

axon
ion
mitochondrion channel
presynaptic
synaptic membrane
synaptic vesicles postsynaptic
endings membrane

presynaptic membrane
postsynaptic membrane
synaptic cleft

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