- [Voiceover] Here is an example
of a typical animal cell.
Now there's 20 million things
you can see going on in here but,
let's start going one by one
and work our way through.
First off, the nucleus.
It's not always found right at dead center,
the nucleus always contains DNA.
DNA is your genetic code.
It's what directs and instructs the cell
on what to do.
It helps make proteins for the body.
We have our rough endoplasmic reticulum,
and then we have our three ribosomes.
So that blue structure,
that's kind of weaving back and forth
with the red dots on it,
those red dots are going to be ribosomes
on the endoplasmic reticulum.
It's called the rough endoplasmic reticulum
because you have all these little bumps,
all these ribosomes on it.
And as you can see,
lot of protein synthesis here.
But you also have some free ribosomes
just kind of floating around.
There's little tiny spheres.
Also more protein synthesis.
As you head out away from the nucleus
a little further,
you get to the smooth endoplasmic reticulum.
Now this is where you have a lot of
macromolecule synthesis, besides protein.
Things like lipids for example, fats.
So that's your smooth endoplasmic reticulum.
Heading even further out,
the golgi apparatus,
or it's known as called the golgi body.
And kind of think of the golgi apparatus
as a packing station.
So to pack things up and then ship them out.
Within the cell or to other cells.
A vesicle, or known as a secretory vesicle.
These vessels can help to carry things
anywhere within the cell
and then potentially release them out of the cell.
Mitochondria,
think of them as the power house of the cell.
Mitochondria produce energy.
Centrioles.
You can always find these in pairs
because the centrioles aid in cell division.
One cell can become two
so each centriole helps to pull half the DNA
towards itself.
Now we have two things,
these peroxisomes and lysosomes.
So top left, you see the term peroxisome.
Kind of looks like a green sphere
with yellow and brown inside.
It's meant to destroy your internal waste.
So it gets rid of things
that the cells are finding toxic.
While bottom right,
you can see the green sphere,
with kind of almost an orangish red inside.
Those lysosomes contain digestive enzymes.
What happens here now is,
any organelles,
which are what all these are,
or any other cell debris,
is destroyed and removed by the lysosome.
Cytosol.
Think of it as jello inside your cell.
It's a semi fluid jell material.
Everything's kind of suspended in it.
So if you've ever made jello and put fruit parts
or any other things inside the jello
and they kind of just stuck in there,
that's what cytosol's like.
Plasma membrane.
That's the external coating,
or covering of the cell.
It's what determines the boundary
from inside to out.
And the cytoskeleton.
Cytoskeleton, it's your framework,
it's what helps provide the shape a cell is.
But besides shape,
it also helps to anchor all these organelles
in place.
So here is a typical animal cell
with all its various organelles inside.
Let's go more information into that nucleus.
Already mentioned, the nucleus contains DNA.
That's your genetic information.
That's what can control the cell functionality
and control production of things like proteins.
So if you look at the surface,
or the structure I should say
of the nucleus.
You'll have these nuclear pores
around the surface.
What those are are simply little tiny holes
that allow information to enter
or leave the nucleus.
But when those nuclear pores are going through
it's a double layer membrane.
So it's two layers thick.
The inside, where all that information is stored,
are in chromosomes, chromatin,
that's your DNA.
What's coming and going is your RNA.
RNA can enter the nucleus,
it can leave the nucleus.
And then usually in the very center of the nucleus,
you have this structure called
a nucleolus.
The nucleolus is more densely packed area
of genetic material.
It's more of a longer term storage.
It's not for the day to day activities.
So the nucleolus, found inside the nucleus.
Ribosomes are where you produce proteins.
It's protein synthesis.
Remember there are two types of ribosomes.
You have free ribosomes,
the ones that are just floating around
inside the cell,
and then you have the membrane bound.
Those are the ones that are found on the surface
of the rough endoplasmic reticulum.
So we have free floating around,
and then bound,
the ones that are
on the rough endoplasmic reticulum
or the rough ER.
So the rough ER is part of the endoplasmic reticulum.
It has ribosomes at the surface.
It's used for protein manufacturing.
But also, protein modification.
And this rough endoplasmic reticulum
is typically the first membrane found
on the outside of the nucleus.
While the smooth ER,
or smooth endoplasmic reticulum
does not have any ribosomes,
it's typically further away from the nucleus
than the rough ER.
Because it does not have any ribosomes,
it's primarily used in lipid synthesis.
Remember, lipids are your fats.
But even though it does not produce
or make protein,
the smooth ER can help to package the protein.
Kind of get in this big bundle
to get ready to ship out.
But where's the protein going?
It's heading to the golgi apparatus,
or called the golgi body.
It's refining your synthesized product.
It's packaging and shipping.
So pretty much, you can think of the golgi apparatus
as like a UPS store, or a FedEx store.
You take your item in,
they're going to make sure it's all set to go,
package it up,
and then ship it out.
That's the golgi apparatus.
Now it can ship to somewhere else inside the same cell
or you might be shipping these products
to different cell completely
in another part of the body.
And the way they are shipped off
are via vesicles.
A vesicle is simply a round sphere of membrane.
So it's this round membranous sphere
that the inside is packed
with all these different products.
So what can actually happen in these vesicles,
they're not just used for shipping though,
they can also use for storage.
So in this particular diagram you see here,
you can see the golgi apparatus in green.
And that has these arrows going up and out.
Well, sometimes it might form and make a peroxisome.
Help them get rid of cell waste,
anything that's formed,
and eventually, getting all together,
breaking it down and releasing it outside the cell.
Or if you go to a lysosome,
this one going to the bottom right.
Lysosomes are filled with digestive enzymes.
If somehow you're able to have a bacterium
enter into your cell,
one that should not be there,
well the lysosome might be able to find it.
It can find the bacteria,
it can then release its digestive enzymes around it,
breaking it down.
And then all those broken down compartments
of the bacteria
are released outside the cell.
By the time they're released,
it's not a bacteria anymore.
It's just broken down chemicals
that once made the bacteria.
So peroxisomes are all these different enzymes
that detoxify, get rid of waste.
Lysosome, digestive enzymes,
break down any foreign particles, like bacteria.
And then that power plant,
the power house of the cell, the mitochondria.
One of the unique features of the mitochondria
is the double membrane system.
You can see from the picture,
how the outer membrane is just for the capsule.
Think about a capsule around a pill or something,
same idea.
But the inner membrane is kind of special.
You can see how the inner membrane
is having all these folds,
these indents and creases.
Any thoughts of why or what those folds are doing?
Those folds are meant to increase surface area.
More surface area means more chemical reactions.
More chemical reactions means more production of ATP.
ATP is the energy source for the cell.
So double membrane,
helping to use oxygen to make ATP.
But when it uses oxygen, or O2,
it's gonna produce or give off CO2,
carbon dioxide.
Well how do we get rid of CO2?
We exhale.
Eventually, from within the cells,
this CO2 can make into our blood
and back into our lungs.
So we can exhale and get rid of it.
With a main function here, generating ATP.
Without ATP, our body's could not function,
our bodies could not move,
our bodies can't work.
It's the energy source that runs all of our cells.
And if your thinking, well I don't eat ATP,
I eat protein, I eat carbohydrates,
I eat lipids.
Sure.
All those different components,
all those macromolecules,
those big molecules,
when you eat them,
they're broken down into smaller molecules.
It's those smaller molecules,
especially glucose
that can go through a chemical process
to produce ATP.
Because ATP is what your cells use.
They cannot use glucose directly.