When it comes down to it, the most magnificent of our organs is simply an electrical and chemical organic machine. Those are the (overly-simplified) basics of neuronal communication. (Alternatively, the interaction can make it less likely neuron B will fire an action potential, but we won't get into how that happens in this article.) The signal can then continue to spread throughout the brain. The influx triggers an action potential in neuron B, and in this way a signal has passed from neuron A to neuron B. This interaction can lead to the opening of ion channels, and the influx of positively charged ions into neuron B.

These neurotransmitters leave a neuron (let’s call it neuron A) and then travel to another neuron nearby ( neuron B), where they interact with small proteins called receptors. When positively-charged ions enter a neuron, they can create an electrical impulse (the action potential) that can travel down the neuron and cause the release of chemicals called neurotransmitters. Action potentials are created when charged particles called ions flow into neurons through tiny openings called ion channels. The electrical signals, known as action potentials, are essential for neuronal communication. Thus, to understand the anatomy of a neuron we’ll talk just a bit about how neurons work, and specifically about how they use electrical and chemical signals to pass messages throughout the brain. While anatomy involves identifying body parts and where they are found, physiology is concerned with how those body parts work.

It makes it a bit easier to grasp the anatomy of the neuron if we talk about some physiology first.

So, while we’ll use an image of the prototypical neuron that is most likely to appear in a textbook in this article, just remember that the brain contains a wide array of neurons, and most of them look quite different from this one. There are neurons that have so many processes extending from them that they look like little bushes (Purkinje cells), others that look a bit like baskets (basket cells), and many others. There are tiny neurons of microscopic lengths and there are neurons that stretch to a meter (about 3 feet) long. That’s because neurons come in all shapes and sizes. It’s important to mention, though, that while there are neurons in your brain that might vaguely resemble the one in the image, there are many more that don’t. This is the image we’ll be using for our discussion of the neuron in this article. If you look in any neuroscience textbook, you’ll likely see an image of a neuron that looks something like the image to the right.

Are neurons only in the brain