Hey there! I’m Alie Astrocyte, and you’re watching the very first episode of Neuro Transmissions!
I’m excited to start this series, and hopefully you are excited to learn something about neuroscience!
Are you ready? Then let’s begin at the beginning with...the neuron.
[Intro music]
If you’ve ever opened up your biology book, you probably know that this is a neuron.
But this...is also a neuron.
And so are all of these.
Neurons come in a variety of shapes and sizes, but they all have one job:
to transmit information throughout your mind and body.
Just like copper wire transmits electricity,
or like telephone lines transmit calls,
or fiber optic cables transmit data so that you can watch this video,
neurons form the necessary connections to make you “go”.
There are billions of neurons in your brain.
Scientists estimate around 86 billion.
Those neurons can each form more than a thousand connections with other neurons,
forming up to 100 trillion connections.
This information superhighway is how YOU exist.
It’s the means by which you are able to move, see, hear,
and even think about the world around you.
But in order to understand something as complex as our senses,
we first need to understand the neuron.
As we saw before, they don’t all look the same, but in general they have
most of the same parts. Let’s go over that.
To begin, we have the cell body.
This wider portion of the cell contains a lot of the bits and pieces of the cell that keep it alive and functioning.
If we zoom in, we see that it houses the nucleus, where your DNA hangs out until it’s needed to make proteins.
It also includes things like the Golgi apparatus,
which helps your cell organize, package, and move around different proteins;
the endoplasmic reticulum, the place where proteins are folded into the correct shapes;
and the mitochondria, which provide energy to the cell.
You don’t need to worry too much about those big words for the purpose of this video.
But if you’d like to learn more about the parts of the cell and what they do, check out some of these resources,
which are also located in the description below.
For right now, just remember that the cell body is where the nucleus lives.
Next we see what look like tree branches extending from the cell body.
These are called dendrites.
Dendrites are generally the “receivers” of information into the neuron.
If we increase our magnification, we see small bumps, called spines, lining the dendrites.
Neurons and other cells communicate via these spines by passing information to them.
This connection is called a synapse. We’ll talk more about synapses and communication in later episodes.
Just keep in mind that dendrites have so many spines and so many synapses that
every neuron receives input from hundreds or thousands of other cells.
There is a LOT of communication going on in your brain!
Back to the big picture! This long, thin piece extending from the cell body is called the axon.
At the top here, we have the axon hillock.
This is the gatekeeper that determines if a signal is strong enough to continue past the cell body.
If a signal makes it past the axon hillock, it shoots down the axon.
Axons can be very short, communicating with cells nearby, or very long
For example, the longest axon in your body runs from your lower back all the way down to your big toe!
The axon can also have myelin wrapped around it.
This acts as insulation, and helps the signal travel faster down the axon.
Myelin is kind of like the plastic that coats the outside of a wire
and it is important for allowing cells to communicate very quickly across your whole body.
Finally, along the axon, and at the end, are synaptic terminals.
This is where the neuron connects with the dendrites of other neurons to transmit information.
And there you have it, a basic overview of the parts of a neuron.
Neurons are the most well known cell in your brain. But, it’s important not to forget the other cell types!
Your brain also contains many tiny blood vessels, bringing nutrients and signals from the rest
of the body to help your brain continue functioning.
There are also cells called “glia”, which literally translates to “glue”.
For a long time, it was thought that these cells only existed to provide nutrients to neurons
But recently there’s been a lot of evidence that these cells influence the way neurons communicate and grow!
Cells like microglia are important for the immune response,
helping your brain fight off anything that might harm it and cleaning up dead cells.
Oligodendrocytes help cells communicate faster by insulating the neurons using myelin.
And my special favorite cells, astrocytes, are these beautiful, starry-shaped cells
that help support neurons and also seem to play a large role in
creating synaptic connections between cells.
So even though we’ll talk a lot about neurons and their communication in your brain,
don’t forget that without those other cell types, the neurons wouldn’t be much good on their own!
Well there you go! If you liked this video, give it a thumbs up
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I’d also love to hear your feedback in the comments below. Thanks for tuning in!
Next episode, we’ll dive into how neurons communicate.
I’m Alie Astrocyte, and until our next transmission, over and out!