The ways in which the words can be meaningfully combined is defined by the language's syntax and grammar. The actual meaning of words and combinations of words is defined by the language's semantics.
A nerve impulse is an electrical signal that travels along an axon. There is an electrical difference between the inside of the axon and its surroundings, like a tiny battery. When the nerve is activated, there is a sudden change in the voltage across the wall of the axon, caused by the movement of ions in and out of the neuron.
Nervous impulses are electrical signals that travel along neurons. The electrical signals cannot travel from one neuron to the next directly. The signal crosses the gap, called a synapse, between cells in chemical form. One neuron releases chemicals in response to an action potential (nerve impulse).The chemicals travel across the synapse and stimulate an action potential in the next neuron. These chemicals are known as neurotransmitters.he signal crosses the gap, called a synapse, between cells in chemical form. One neuron releases chemicals in response to an action potential (nerve impulse). The chemicals travel across the synapse and stimulate an action potential in the next neuron. These chemicals are known as neurotransmitters.