So that brings us into looking at the endomembrane system.
So these ribosomes, as I've mentioned, could either be bound,
and they're bound to the endoplasmic reticulum
or external nuclear membrane but mainly
the endoplasmic reticulum. Or they could be free floating.
And that all depends on whether
we are producing proteins to stay or to go.
Let's assume we're making a protein to go, for example, insulin.
We are a pancreatic beta cell producing insulin.
We don't need the insulin. We need to send the insulin out
into the blood so that they can circulate
and pick up or open the gate
so that sugar can be removed from the blood, right.
So, no need to have it here,
we've got to send it to go.
So that protein would be manufactured by
ribosomes attached to the endoplasmic reticulum.
This new protein is produced, and it's packaged into a vesicle.
That vesicle is then going to be transported to the transportation
center or the shipping center which is the Golgi apparatus.
I think of the Golgi apparatus as your FedEx or DHL or whatever.
There has got two sides to it. There is a cis face and a trans face.
And you drop off your stuff on one side,
and then they repackage it and put it in the correct vehicles,
and it will be sent out on the other side in their vehicles,
and they'll drive it to the destinations.
So the vesicle is then delivered to the cell
and exocytosed out of the cell.
Now we've dropped off this insulin on the outside of the cell
and it will float around until it gets to the blood.
And then it's in the blood and it can have its effect.
So mission accomplished.
So a closer look at each of the components of
this endomembrane system, endomembrane transport system.