Okay, let's talk about partitioning and why we want to have membrane structures within the cell.
So, cell membrane and other membranes within the cell.
Let's first start by talking about the cell membrane cuz this is probably the most important,
because it separates inside the cell from outside the cell.
And why this is so important is, if we talk about homeostasis
and maintaining an internal environment within the cell,
we need to have some sort of separation mechanism to keep that inside
and separate that from outside.
However, each portion of the cell or its organelles will have various membranes associated with them.
The endoplasmic reticulum is one, and in this endoplasmic reticulum
which could be rough or smooth, is often times where protein synthesis is taking place.
This is also where you could be packaging some of the cell secretions that may occur.
The Golgi complexes, kind of an extension of the endoplasmic reticulum,
where further processing takes place,
and eventually, you'll get some budding of various vesicles
and that would be what out secretion mechanisms will be.
We also have various smaller cellular structures such as lysosomes and peroxisomes.
These are located close to the cell membrane, just on the inside.
And these are being involved with breaking down either via enzymes and lysosomes
or via reaction oxygen species with peroxisomes.
The mitochondrial membrane is the final kind of organelle structure membrane
that we'll talk about. It's a little bit more specialized. In fact, it has a dual membrane structure.
And so, the first portion of the membrane allows for some things to move in and out,
but then you have a second membrane structure that is more --
or separate structures to a little bit greater degree.
And this will be important for such things as oxidative phosphorylation and production of energy within the cell.
The nuclear envelope is another kind of partition that we have.
It is not exactly like the other cell membrane structures.
It has some larger pores in it that allow for some molecules to move in and out,
and that is helpful for signaling and trafficking.
The final thing that we have is a vesicle membrane or -- and these vesicles usually
are budded off from things like the Golgi apparatus and will eventually dock
and fuse into the cell membrane, spilling its contents out into the extracellular environment.
Okay, so now, let's talk a little bit about why in the world you have partitions anyway.
And I think the best way to think about why partitioning things within a cell,
is think about your own apartment or your own house.
Why do you have walls within your particular apartment or house?
And why would that be important or how is that sometimes helpful?
So, why have these partitions?
Well, I think this basically occurs often when you want to do a specific task within a certain room.
For example, cooking.
Sometimes it's advantageous to cook within one room and keep that separate from the rest of the house.
Maybe you're making something that has a certain aroma
or a smell to it that you want to keep within that room.
Or maybe you have certain tasks that you want to do
at other parts of the house or apartment, such as sleeping.
But yet, you have an apartment mate or you have another person that's living
with you that that person is not ready to go to bed yet.
So, by partitioning out that, it's easier to have one function occurring such as sleeping.
So, how are these particular partitions constructed?
Well, you're gonna have an inner wall and outer wall,
and as you know, usually you have thicker outer walls than you will have inner walls.
But what are these particular membranes made of?
So, we'll spend a couple minutes talking about how they're specifically made up,
what their sizes are, and how that structure affects its function.