Psychology – Gleitman
100 billion. There is no way of getting more; once lost, a neuron can never be replaced.
The gap between the axon terminals of one neuron and the dendrites and cell body of another is called the synapse; this is the gap the nerve impulse must cross
for one neuron to stimulate the next. Such junctions often involve many more than two cells, especially in the brain.
Types of Neurons:
Some neurons are attached to specialized receptor cells that can respond to various external energies, suhc as pressure, chemical changes, light and so on. These
receptor cells can translate or transduce such physical stimuli into electrical changes, which will then trigger a nervous impulse in other neurons. Receptor cells
are like money changers, exchanging the various energies impinging from the other world into the only currency acceptable within the nervous system- the
nervous impulse.
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