 All right, so smell is a little bit different than our others. Actually, for several reasons, smell is different. First of all, one of the things that we already established with special sensory organs, that they have, like the organ itself, the tongue, the taste bud, is the structure that receives the information is sensitive to the stimulus and then it delivers that information to my sensory neuron, which then carries it to the brain. In the case of smell, it's not that way. So the anatomy of smell is basically you have these little sensory neurons and they're embedded in the epithelium lining the nasal cavity. Look at this cross-section of nose, of skull, so that we can actually see you can see your nasal conchie. You can see the input, the external nary, so we can get air in. And then you can see right here, all of these little yellow fibers coming down and embedding themselves in that nasal epithelium. Notice that these, they are neurons. Do you agree with that? They are sensory neurons. They have little epithelial, I think they call them cilia. They're little extensions that are reaching out, increasing the surface area. Those little extensions have receptors on them. Similar to taste, they're actually picking up chemical stimuli. So when you take a deep breath of air, there are molecules, atoms, things in the air that they actually, in order to stimulate a smell, a perception of smell, they have to connect with the receptors on the neurons embedded in the nasal epithelium. Now, once they bind, here's a little molecule that comes in and binds to the receptor found on one of these neurons. It's going to stimulate a message, an electrical message that's going to pass through the cell and down its axon or whatever you want to call this thing, and then look where it goes. First of all, who did it go through? Oh, oh, who is this, my friends? That's the ethmoid bone, yes? And what were all those holes called? The cribriform foramina. That is the name to name your kid. So they pass through the holes. Most of the time, your body doesn't just have some random hole somewhere. If we're going to have a hole, let's send something through it. So we send these neurons through the hole. They've been activated. They're bringing the message to this structure. Now, look at the big picture. Look at what this structure is. There it is. And now we've just blown it up. Boo-lu, magic. Your lingual epithelium, it's not lingual in there. It's olfactory epithelium. Synapses on these guys. Look, holy neuron, crazy madness. That's when the message gets sent to the brain. Through this thing, what is that thing? What is this thing of which you speak? Hmm, hopefully you figured it out already. That is cranial nerve number one. That's the olfactory bulb. Would you agree? Since this is actually the neurons in the olfactory epithelium are actually receiving the information and synapsing with the olfactory bulb, where is the olfactory bulb? It's in brain. It's in the cranium. It's not even coming out into the peripheral nervous system. I mean, into the periphery, which means it's actually not even a nerve at all. Does that blow your brain? It's actually a tract. Do you agree with that? This can't really be called a nerve either because these guys are just like this array of neurons bringing information in. But that's kind of an interesting thing. Okay, so are you comfortable with the anatomy? We're not looking at slides. We're knowing that we have neurons, sensory neurons, embedded in your olfactory epithelium that send the message to the olfactory nerve. And these guys say, hey man, take the message to the brain. Shall we see how that happens? What a great idea. Let's do it.