Final answer:
A neuron receives neurotransmitters, leading to a positive charge shift inside the cell; reaching a threshold, this initiates an action potential which carries the signal to other cells.
Step-by-step explanation:
The process described involves a neuron receiving an incoming signal and turning it into an action potential. When the neuron's dendrites capture neurotransmitters released by an adjacent neuron, they trigger the opening of sodium ion channels. This permits an influx of sodium ions into the cell, making the internal charge more positive. Reaching the threshold of excitation, this triggers the action potential—a rapid electrical signal that travels along the axon to the axon terminals. The action potential is then passed on to other neurons or cells at the synapse. This transient burst of electrical activity is how neurons communicate within the neural tissue and is a fundamental aspect of nervous system function.
The figure illustrates the process of an action potential in a neuron. When a neuron receives signals at the dendrites, small pores or gates open on the neuronal membrane, allowing sodium ions (Na+) to move into the cell. This influx of positive ions increases the internal charge of the cell, and if it reaches a certain level called the threshold of excitation, the neuron becomes active and an action potential is initiated. This electrical signal then travels down the axon to the axon terminals, allowing the neuron to communicate with other cells.