Dr. Sarah Al-Izki: So, my name is Sarah and I work for Queen Mary. I'm a post-doctoral researcher and I work on multiple sclerosis.

Today I'm going to make the axon, or the nerve, and I'm gonna show you the myelin that wraps itself around the axon and how it's damaged [unintelligible] disease.

So, I'm going to start with a cauliflower, which is what I'm going to saw represents the brain. I'm just going to take off these leaves and throw them away.

So, this is the brain. And if I cut this in half, that's what a brain looks like inside when it's cut in half. And if you imagine, in the brain, it's full of nerve cells and axons. So each area of the brain is full of millions and millions of axons, so I'm just going to take out one area of this cauliflower and I'm going to show you what an individual axon looks like.

I'm going to make my axon now. So I'm going to use a strawberry, which is going to be the cell body.

That's your cell body there. The myelin that wraps itself around the axon is a fatty tissue, so for that I'm going to use cheese straws, because they're fatty. So, I'm just going to cut them into pieces and I'm going to feed them through.

And when the myelin wraps itself around the axon, it leaves spaces, so you can see while I'm putting the cheese on, the spaces between each myelin. And these spaces are called the Nodes of Ranvier.

And when a signal passes, if you can imagine you've got your brain here and you want to send a nerve signal from your brain, say, to your leg, this is sent through an axon. And the nerve signal, which is an electrical impulse, will jump from one set of myelin to the next. So, these Nodes of Ranvier act as; you know, they speed up the signal so they make it faster.

So, I'm going to use a blueberry to represent the nucleus that's found in a cell body.

So, the way the cell works is, it's going to pass its signal from this cell to another cell. So, to represent the other cell I'm going to use a slice of melon. So, I'm just going to cut a slice off.

So, this is one part of the cell (the slice of melon). And for the other part, I'm going to use a butternut squash. So, I'm just going to cut that.

So, the reason I've used a butternut squash with all the seeds is because when a signal, when an electrical impulse goes from one axon to the next, it releases neurotransmitters. So these little seeds of the pumpkin represent neurotransmitters.

So, just to finish off and show you what I've made, you've got the brain, which is the piece of cauliflower cut in half. And in the brain is full of little nerves and those nerves is what I've made here. It's what we call an axon.

So, we have your cell body, which is your strawberry, and your nucleus, which is your blueberry. And the axon here, which is the skewer stick. And the cheesy straws; the cheesy bits here, that's what we call myelin, which is a fatty sheath that surrounds the axon.

And a nerve impulse, or an electrical impulse that passes the signal from the brain to the rest of your body, is passed along this axon. And the way it works is each axon terminal (so, from this side to this side) is; I'm going to represent here in the butternut squash and the slice of melon.

So, these are two axon terminals that are now joined together, and the signal is passed, and this is done by the neurotransmitters, which I'm representing here using the butternut squash seeds. And these are released into the space between both axon terminals and the signal is passed from the brain to the rest of your spinal cord.

Film by Alison Thomson, March 2011. Somehow Related. Funded by UnLtd.

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