A lysosome is a eukaryotic cell organelle.
Structure of the lysosome
The lysosome is a small spherical structure (a vesicle) delineated by a lipid membrane and located in the cytoplasm of eukaryotic cells. The membrane contains ion channels (proton pumps) which allows active intake of H+ ions in order to maintain an acid pH (between 3.5 and 5) within the lysosomal vesicle.
Role of the lysosome
The lysosome acts as a cell dustbin where non-functional molecules are removed by digestion. The lysosome contains hydrolases, enzymes intended to degrade intracellular molecules. They are only active in an acid pH, hence the low pH in the vesicle.
Diagram of a typical animal cell with its organelles: 1. Nucleolus; 2. Nucleus; 3. Ribosome; 4. Vesicle; 5. Rough (or granular) endoplasmic reticulum also called the ergastoplasm; 6. Golgi apparatus; 7. Cytoskeleton ; 8. Smooth endoplasmic reticulum ; 9. Mitochondrium ; 10. Vacuole ; 11. Cytosol ; 12. Lysosome ; 13. Centriole. © MesserWoland et Szczepan1990, Wikimedia, CC by-sa 3.0