 Okay, so now we're going to get a full-body model of the spinal column itself and the respective plexi Okay, so starting up here at the top So the first thing we can see the frontal lobe of the brain and you can see some of your cranial nerves We'll cover cranial nerves later, but this is the olfactory nerve and the olfactory bulb Okay, we can also see our optic nerves. These are two large nerves You can see immediately sticking out by the frontal lobe of the brain My pons It's the swollen region here And the medulla oblongata is directly below that Okay, and that leads into the individual spinal cord itself, which is this white structure running down the center Now branching off of the spinal cord are of course nerves And we can group these nerves into plexi These plexi are just groups of nerves that are all working together interacting with each other So the first part from about right here up is my cervical plexi So if you remember from your bones, these are our cervical vertebrae. Well, the first part is the cervical plexi The second part of the cervical vertebrae branch to make these long Structures here that going off into the arms. That's our brachial plexi When we move down, you can see the intercostal nerves. So the nerves coming off of those thoracic Vertebrae, they're not actually plexi. They're just individual intercostal nerves Moving on down Okay, so now we're in the lumbar vertebrae, so we have our lumbar plexi And finally Moving all the way down here in the sacrum. So the sacrum sits down here in our sacral plexi And we'll accumulate into this single nerve here the largest nerve in the body the sciatic nerve Okay, so looking back So again our whole spinal cord here. Well, if we followed the spinal cord, okay It starts to widen right in this region right here And it's called the conus medullaris So you can find it easily so it forms this terminal here So it kind of makes it look like a little bit of a cone So a widened base and it comes to a point. It's what a cone looks like, right? So that's your conus medullaris Then it's going to branch out to these striated Regions here called the cata equina, which literally means horses tail cata being tail equina being horse The last part of this that we can see Is this sympathetic trunk which is this yellow line with the pink dots Which are made up of the chain ganglion