Now, the way the cholesterol actually gets in the cells is interesting.
The reason that cholesterol is in the LDLs
isn’t to cause heart attacks,
but rather to provide a delivery mechanism for cells to get cholesterol.
Cells have on their surface
a receptor that recognizes and binds the LDLs.
If the cell is needing cholesterol,
it will grab an LDL out of the blood stream
and internalize it in this process that you can see here.
So we first have a binding process, followed by endocytosis.
And this process is called, receptor-mediated endocytosis, for this purpose.
You can see the steps happening inside.
There’s actually an unpacking of the LDL that occurs and the goodies inside,
including the cholesterol are used by the cell.
There’s a recycling that happens where the remnants that aren’t used by the cell
are then exported back out of the cell,
and at the mean time the cell has gotten cholesterol
that it needs for the purposes of making membranes.