In this video I want to explain in simple terms, what a virus is
it's a video for parents to show to their kids or to watch themselves and then reinterpret for their kids or
or really
It's for anyone who wants a simple explanation of what a virus is.
To understand what a virus is, you need to understand what a cell is.
You may have heard of cells before: every living thing is made of cells and they're tiny
You are made of trillions of cells
That's how small they are.
If you wanted to see a cell you need to look under a microscope.
So if you had a really powerful microscope
Then you look to your skin
You'd see that your skin was made of lots of these little blobs and they're cells.
because you're a child, you're growing.
Very slowly you're getting bigger and bigger and bigger as time goes on.
I'm not growing anymore because I'm an adult and I'm as big as I'm gonna get.
The way you grow is by the number of cells in your body going up.
So the more cells you have the bigger you become and the way you get more cells
Is that the cells inside your body
Get a little bit bigger until they split in two
So if you look under a microscope, you might catch that happening
You'll notice one of the cells getting bigger and bigger and bigger until it splits into two cells
So now you have more cells than you did before and that's happening all through your body as you grow
Even though I'm not growing it's still happening in my body as well, because
Sometimes cells die and they need to be replaced by new cells
So cells are growing and splitting in two in my body as well.
How are cells able to do this?
Well, you can think of a cell a bit like a factory full of machines
But they're not like machines you've ever seen before they're these weird knobbly things and they're just kind of floating around in there
bumping into each other when they bump into each other they change shape
It's a strange place inside a cell but just like a normal
Factory a cell brings in raw material and turns those raw materials into products
Things that your body needs to function and we call those raw materials nutrients
And you know you get nutrients from the food that you eat.
As one of your cells gets bigger and bigger and it's ready to split in two
This factory inside does something amazing
It builds a copy of itself
So that there's two of every single machine
That makes up the factory and when it splits into two
One copy of the factory is inside one cell and another copy is in the other. Isn't that amazing?
It's a bit like buying a 3D printer and then using it to print another 3D printer
That's what your cells do all the time when they grow and divide in two.
How do these machines inside your cells know what to make and when to make them?
Well inside every single one of your cells is
Something a bit like an instruction manual you might have heard of it: It's called DNA.
But DNA is not like any instruction manual you've ever seen before
imagine taking an instruction manual:taking all the sentences
inside that manual and putting them in one huge long line
So you've got this huge chain of letters and words.
except for DNA those letters are actually clumps of atoms
So DNA tells the machines inside the factories - inside your cells -
what to make and when.
So that's everything we need to know about cells
Let's talk about viruses.
Viruses are even smaller than cells.
To see just how small the virus is compared to the size of your cells
Imagine this is one of your cells. Well, then a virus would be just that big
In fact at this scale if you look closely you'd be able to see the individual atoms that the virus was made of
Let's have a look inside one!
This is coronavirus and when you look inside there's this curly wurly thing
and that is the instruction manual for the virus.
So a bit like we've got DNA in our cells
That's the instruction manual for our cells
Viruses have this instruction manual too.
The instruction manual for coronavirus has a slightly different structure to DNA,
so we call it RNA but it's the same idea.
You'll notice that it's very cramped inside the virus.
There's not much room for anything really.
There's definitely no room for any machines. Like there are inside cells
So there's no factory inside a virus: a virus doesn't have what it needs to make copies of itself, because there's just no room.
The only way for a virus to make copies of itself is to get inside your cells and use the machinery inside your cells to make copies
So, how does that happen?
Well suppose someone who is suffering from corona virus coughs
So they allow all these tiny droplets of water into the air and these droplets of water have corona virus particles in them
So if you were to breathe in some of these droplets they would end up in your mouth and in your throat
Catching corona virus in this way
- by breathing in someone's cough -
we think only really happens when you're right up close to someone.
Which is why we're doing this social distancing thing
So it's not something to be scared of so long as you're keeping your distance
Actually the most common way to get corona virus scientists think is by someone with the infection
Coughing and then those droplets landing on surfaces
Or maybe they cough into their hands and touch surfaces like door handles
And then when you touch the door handle that's got the virus on it
The virus goes onto your hands and then maybe you touch your mouth or you pick up some food and eat it
Which is why everyone's telling you to wash your hands
it's really important to wash your hands often and to do it really well, but in any case
whatever way it happens if the virus gets into your airways and it's going to start bumping into the cells that line your
Airways and if you look at the outside of a virus
You'll notice all these funny sticky-out bits that have been coloured in purple in this picture
These knobbly bits are good at sticking to certain types of cell in the case of corona virus
These knobbly bits on the outside are good at sticking to the types of cells that line our airways and when a virus
Sticks to a cell it then merges with the cell
So now this curly wurly instruction manual for the virus is inside
One of your cells, so maybe you can guess what happens next
Inside your cells you've got these machines and they're looking for things to build: They're looking for instructions
What should I build next?
And normally those instructions would come from your DNA
But now you've got this virus instruction manual floating around
and one of these machines is just going to bump into those instructions and start reading those instructions
And at that point the machines inside your cell start to build copies of the virus
so your cell fills up with copies of the virus and they start to emerge from your cell.
And now they're floating around in your airways.
And now you start to cough
and you'll start spreading viruses through the air for the next person to breathe in
So, there you go: That's how viruses work.
If your kids are interested to know more about germs
Then I'd love you to take a look at the bacteria book written by me "Gross Germs, Vile Viruses, and Funky Fungi"
there's loads of cool stuff in there and
It's available in lots of different languages. For example:
"El libro de las Bacterias"
Apparently "Hongos chungos" is very funny, but no one's been able to explain exactly why
All the links are in the description for where you can buy it
If you're looking for stuff to do with your kids during lockdown
then I've got a couple of other books: "How to Be a Sientist" and
"Science is Magic" full of experiments you can do at home with things you've already got at home
I've got a new book coming out available for pre-order called "Wild Scientists".
It's called "Clever Creatures" in America
I'll put links to that as well
It's about all the amazing science. You can see animals and plants doing
Out there in the wild
Yeah, check it out. It's in the description
Thanks for watching. I hope the exploration was useful to you and
I'll see in the next one: Bye