00:01
So, that's been potocytosis and pinocytosis, cell drinking.
00:05
Next up is phagocytosis.
00:08
And phagocytosis is generally done only by specialized phagocytes or cells that eat.
00:14
To a limited extend, every cell has the capacity to eat relatively small things.
00:20
And we will talk about subsequently, eating apoptotic bodies.
00:25
Small, little buds that come off in apoptotic or cell
that is dying due to program cell death.
00:33
So, phagocytosis will be a lot of cells.
00:35
But mainly, it's macrophages and neutrophils
that do the major job of eating the large things like bacteria.
00:42
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.
01:07
This is just a pseudo-colorized scanning electron micrograph of a neutrophil.
01:13
They are in yellow, that's eating a Bacillus anthracis, a bacteria.
01:19
One of the forms of bacteria. This is one that actually causes anthrax.
01:22
So, you can see that it -- you can actually eat something
that's substantially larger than you are under appropriate circumstances.