What are the five key parts involved in impulse transmission?

The five key parts involved in impulse transmission accurately represented in the chosen answer are rest, depolarization, repolarization, hyperpolarization, and the refractory period.

Rest refers to the resting membrane potential of the neuron, where it is polarized and ready to respond to a stimulus. During depolarization, the neuron’s membrane potential becomes less negative due to the influx of sodium ions, which is the initial phase of generating an action potential. Following this, repolarization occurs, where the membrane potential is restored to its resting state as potassium ions flow out of the neuron. Hyperpolarization may happen after repolarization, making the inside of the neuron even more negative than the resting potential. Finally, the refractory period is crucial as it is the time during which the neuron cannot fire another action potential, ensuring that impulses move in one direction and providing a recovery phase for the neuron.

The focus of the other choices does not align properly with the core elements of impulse transmission. Some mention neurotransmitter activity, which, while part of synaptic transmission, does not detail the phases of action potential propagation. Others include terms that represent concepts or processes that are not the direct phases of impulse transmission in a single neuron.