Ciechanover Figure 2.
The four digestive processes mediated by the lysosome:
(i) specific receptor-mediated endocytosis, (ii) pinocytosis (non-specific engulfment of cytosolic droplets containing extracellular fluid), (iii) phagocytosis (of extracellular particles), and (iv) autophagy (micro- and macro-; of intracellular proteins and organelles)
(with permission from Nature Publishing Group. Published originally in Ref. 83).