2-Minute Neuroscience: The Neuron Welcome to 2 minute neuroscience, where I simplistically explain neuroscience topics in 2 minutes or less. In this installment I will discuss the neuron. This is a brain. Estimates vary but right now the best guess seems to be that our brains contain around 85 billion neurons. The neuron is a nerve cell and is the primary functional unit of the nervous system. This is a generic image of a neuron. Neurons actually come in all shapes and sizes but this is the prototypical version of a neuron that you'll often see in a textbook. The structures extending from the left side of a neuron that look a little bit like tree branches are called dendrites. Dendrites are the area where neurons receive most of their information. There are receptors on dendrites that are designed to pick up signals from other neurons that come in the form of chemicals called neurotransmitters. Those signals picked up by dendrites cause electrical changes in a neuron that are interpreted in an area called the soma or the cell body. The soma contains the nucleus, which contains the DNA or genetic material of the cell. The soma takes all the information from the dendrites and puts it together in an area called the axon hillock. If the signal coming from the dendrites is strong enough then a signal is sent to the next part of the neuron, which is called the axon. At this point the signal is called an action potential. The action potential travels down the axon, which is covered with myelin, an insulatory material that helps to prevent the signal from degrading. The last step for the action potential is the axon terminals, also known as synaptic buttons. When the signal reaches the axon terminals it can cause the release of neurotransmitter. These purple structures represent the dendrites of another neuron. When a neurotransmitter is released from axon terminals, it interacts with receptors on the dendrites of the next neuron, and then the process repeats with the next neuron.