[MUSIC] There are four parts to neurons. Neurons have four parts. The first is the cell body, also called the Soma. And this is the part that all cells have, this is cell central. There's the nucleus is here with the DNA. This is like city hall, it's gonna give out all the orders. There's a manufacturing plant here where proteins are made. There is a power plant here. So this is really the place that keeps the cell going. It makes all the material for the entirety of a neuron which it can be, as we said in the last segment, very, very long. Very large. So the cell body has coming out from a number of dendrites, and these dendrites branch. And they continue to branch. And they can branch two, three, four, five times. And so, that makes a tree which we call the dendritic arbor or the dendritic tree. And these dendrites are responsible for gathering in information. They're the sentries. They are the ears of the cell, of the neuron. They're taking in all information. So information is going in to the dendrites, in to the cell body to a certain extent, but really in to the dendrites. So what do we do with all that information? Well, the cell is going to process it, sum it up. And then send it out through one axon. There's one axon. And while these dendrites are very local, they're gonna have a local distribution. This axon can go far, far distances. And so this can go a meter, easily. So this is an axon, and it's gonna carry the information along the length of it. But then what? So you have to get to a terminal, which is a communication center. Which is gonna take that information and give it to the next cell in line. And if we just blow up this area right here. What we see is that there's a synaptic terminal, which is separated by a space. And then contacts another cell. So the information transfer is in this direction, from the axon to the next cell. And this point of information transfer is called the Synapse. This cell, this second cell, the cell that the neuron is talking to. Can be any of a variety of cell types. It can be another neuron. So most of the neurons in the brain, they just talk to other neurons. There's a big internal conversation going on there. So neurons talk to neurons. But neurons also, go talk to muscles. And neurons talk to glands. And neurons talk to the cardiac, to the heart, to the cardiac muscle and so on. Okay. In the next segment, what we're gonna do is look at the variety. I've drawn one cell, but cells look really different. Even in the same place, they look really different. And we'll look at some of the variety of neurons and talk a little bit more about their uniqueness. [MUSIC]