What is the primary function of the axon in a neuron?

The primary function of the axon in a neuron is to send signals. Axons are long, slender projections of a neuron that transmit electrical impulses away from the cell body toward other neurons, muscles, or glands. This process is critical for communication within the nervous system. When a neuron receives a signal, it integrates that information and, if the signal is strong enough, the axon generates an action potential—a rapid electrical signal that travels down its length. The action potential then reaches the axon terminals, where it triggers the release of neurotransmitters to communicate with other neurons.

In contrast, the roles of receiving signals, storing energy, and processing information are associated with different parts of the neuron or other cells within the nervous system. Dendrites, for instance, are responsible for receiving signals and relaying them to the cell body. Storing energy is not a primary function of neurons as they primarily rely on glucose and oxygen for energy, while the processing of information is more generally a function of the neuron as a whole rather than specifically attributed to the axon. Therefore, the axon's specialized role in sending signals is what makes it crucial for the functioning of the nervous system.