Kaplan Nursing Entrance Practice Exam

What is the function of neurotransmitters in the nervous system?

1. To generate electrical signals

2. To convert membrane potential

3. To maintain resting potential

4. To assist in muscle contraction

The correct answer is: To convert membrane potential

Neurotransmitters play a crucial role in transmitting signals within the nervous system, which is essential for communication between neurons. While they do not generate electrical signals themselves, they facilitate the conversion of an electrical signal in one neuron into a chemical signal that can be understood by another neuron. When an electrical impulse (action potential) reaches the end of a neuron, it triggers the release of neurotransmitters from vesicles. These chemical messengers then cross the synaptic gap and bind to receptor sites on the next neuron, which can lead to changes in the membrane potential of that neuron. This process ultimately influences whether the next neuron will generate its own action potential based on the summation of excitatory and inhibitory signals. Therefore, the function of neurotransmitters is critical for the conversion of the electrical signal into a chemical signal and back into an electrical signal again in the receiving neuron.