Lysosomes and peroxisomes both break down substances within the cell. Learning which substances they break down and in what contexts they function will make it easier to tell them apart.
- fuses with food vacuoles and membranous vesicles
- contains hydrolytic enzymes for digestion
- digests macromolecules
- breaks down damaged organelles
- built with proteins from the rough ER
Lysosomes digest substances such as macromolecules, once they fuse with membrane bound vesicles. In this way lysosomes help break down substances which can be recycled for other cellular needs. For example, as amoebas engulf food via phagocytosis, part of the cell membrane forms around it as it moves into the cell. The membrane enclosed food is called a food vacuole. A lysosome will then fuse with the food vacuole to digest its contents.
- break down substances via oxidation
- break down fatty acids
- built with proteins from ribosomes in the cytosol
- do not bud off of the endomembrane system
Peroxisomes can increase in number by dividing once they grow large enough.
Peroxisomes safely sequester and break down toxic substances, including hydrogen peroxide and products of oxidation, from the cell and other endomembrane organelles.