Summary:
- Cells of the immune system consistently destroy pathogens by essentially "eating" them.
- Vesicles or other bodies in the cytoplasm move macromolecules or large particles across the plasma membrane.
- There are two types of vesicle transport, endocytosis and exocytotic vesicles.
- Both processes are active transport processes, requiring energy.
- The plasma membrane folds over the substance and it becomes completely enclosed by the membrane.
- At this point a membrane-bound sac (vesicle) pinches off and moves the substance into the cytosol.