The action potential moves down the axon beginning at the axon hillock. The membrane potential will move from a negative, resting membrane potential, shown here as -65 mV, and will rapidly become positive and then rapidly return to rest during an action potential. The action potential is a brief but significant change in electrical potential across the membrane. During the action potential, the electrical potential across the membrane moves from a negative value to a positive value and back.Īnimation 1.1. The action potential is a very brief change in the electrical potential, which is the difference in charge between the inside and outside of the cell.

The axon transmits an electrical signal, called an action potential, from the axon hillock to the presynaptic terminal where the electrical signal will result in a release of chemical neurotransmitters to communicate with the next cell. ‘Axon’ by Casey Henley is licensed under a Creative Commons Attribution Non-Commercial Share-Alike (CC-BY-NC-SA) 4.0 International License. The axon terminates at the presynaptic terminal. The axon is a long single projection that begins at the axon hillock, the region between the cell body and the axon. Axons can branch in order to communicate with more than one target cell. The axon hillock is located where the cell body transitions into the axon. The axon, highlighted in green, is usually a long, single process that begins at the axon hillock and extends out from the cell body. ‘Soma’ by Casey Henley is licensed under a Creative Commons Attribution Non-Commercial Share-Alike (CC-BY-NC-SA) 4.0 International License. These organelles include mitochondria, endoplasmic reticulum, and Golgi apparatus. The cell body, or soma, of the neuron contains the nucleus and organelles that are commonly found in other cell types and are important for basic cellular functions. The organelles, illustrated in the inset box, in the soma are responsible for cellular mechanisms like protein synthesis, packaging of molecules, and cellular respiration. The nucleus houses the DNA of the cell, which is the template for all proteins synthesized in the cell. The cell body, shown here in green and also known as the soma, contains the nucleus and cellular organelles, including endoplasmic reticulum, Golgi apparatus, mitochondria, ribosomes, and secretory vesicles. ‘Dendrites’ by Casey Henley is licensed under a Creative Commons Attribution Non-Commercial Share-Alike (CC-BY-NC-SA) 4.0 International License. Some dendrites have small protrusions called spines that are important for communicating with other neurons. Their function is to receive information from other neurons. Spines increase the surface area of the dendritic arbor, which may be an important factor in receiving communication. Spines, illustrated in the inset box, are the sites of some synaptic contacts. Dendrites may also have small protrusions along the branches known as spines. The number of inputs a neuron receives depends on the complexity of the dendritic branching. They are the main target for incoming signals received from other cells. Dendritesĭendrites, shown here in green, are processes that branch out in a tree-like fashion from the cell body. ‘Neuron’ by Casey Henley is licensed under a Creative Commons Attribution Non-Commercial Share-Alike (CC-BY-NC-SA) 4.0 International License. The axon begins at the axon hillock and ends at the presynaptic terminal, which can branch into multiple terminals.

Dendrites branch out from the cell body, where the nucleus is located. The typical neuron consists of the dendrites, cell body, axon (including the axon hillock), and presynaptic terminal. The function of the neuron is dependent on the structure of the neuron. Their main function is to send electrical signals over short and long distances in the body, and they are electrically and chemically excitable. Neurons are the basic units of the brain.

Dendrite labeled