The degradation of cell ingredients takes place mainly in lysosomes. The most important and also the best known degradation pathway is autophagy, where a sequestrating membrane separates a part of the cytoplasm so forming an autophagic vacuole. Degradation of the autophagic vacuole ingredients starts after the fusion of the autophagic vacuole with a lysosome. Some cytosolic proteins are introduced to a lysosom by a heat-shock protein (Hsp 70) in a process called carrier mediated proteolysis. Another pathway of lysosomal protein degradation is crinophagy where the secretory vesicles containing newly synthesised proteins fuse with the lysosomal membrane instead of fusing with the plasma membrane. Part of the proteolysis is localised in the cytosol and is known as nonlysosomal proteolysis. In this degradation, large protein complexes proteasomes and protein ubiquitin are involved. The degradation products are reused for the synthesis of new cell components. Thus degradation processes are involved in recycling of the cell ingredients.