Video Transcript
A key structure of a nerve cell, neuron, is the axon. What is the primary function of the axon? (A) To receive electrical impulses from other neurons and transmit them toward the cell body. (B) To insulate the dendrites and increase the speed at which an action potential is conducted. (C) To transmit impulses from the cell body to the axon terminals, ready to be passed to other neurons.
This question asks about the key structures of nerve cells. So, to answer, let’s review what a neuron is, its key structures, and their functions.
Nerve cells, or neurons, are the primary cells that are found in the central and peripheral nervous systems. The neuron has a very unique structure that is different from all other cells in the body. The basic structure of neurons includes the dendrites, the cell body, the axon, and the axon terminals.
The dendrites are numerous cell projections that receive action potentials from other neurons. The dendrites are connected to the cell body, or soma, which is where the nucleus of the cell is housed and integrates the signals from the dendrites.
The integrated signal is then conducted from the cell body to the axon. The axon is the main conducting unit of the neuron, which helps carry the action potential long distances. Since axons can vary greatly in length, they’re often surrounded by the myelin sheath, which helps to insulate the axon and increase the speed of signal transduction.
The end of the axon is called the axon terminal. The axon terminals are the part of the neuron that transmit the action potential to other neurons by converting it to a chemical signal and sending it across the synaptic cleft, propagating the action potential.
Now that we have reviewed the various structures of the neuron, we recall that the axon carries the action potential away from the cell body and toward the axon terminal. With this information, we’re now ready to answer the question. The primary function of the axon is to transmit impulses from the cell body to the axon terminals, ready to be passed to other neurons.
