So, that's been potocytosis and pinocytosis, cell drinking.
Next up is phagocytosis.
And phagocytosis is generally done only by specialized phagocytes or cells that eat.
To a limited extend, every cell has the capacity to eat relatively small things.
And we will talk about subsequently, eating apoptotic bodies.
Small, little buds that come off in apoptotic or cell
that is dying due to program cell death.
So, phagocytosis will be a lot of cells.
But mainly, it's macrophages and neutrophils
that do the major job of eating the large things like bacteria.
They will internalize it, not using clathrin and not using caveolin,
but by a different pathway, and they will engulf that large thing in membrane,
internalize it, turn it into a phagosome,
and then they will fuse that with a lysosome where then, proteases
and other mediators can cause the degradation of whatever has been ingested.
This is just a pseudo-colorized scanning electron micrograph of a neutrophil.
They are in yellow, that's eating a Bacillus anthracis, a bacteria.
One of the forms of bacteria. This is one that actually causes anthrax.
So, you can see that it -- you can actually eat something
that's substantially larger than you are under appropriate circumstances.