An endosome is a eukaryotic cell organelle.
Structure of the endosome
An endosome is a small spherical structure (a vesicle) which is delineated by a lipid membrane and located in the cytoplasm of eukaryotic cells close to the cell plasma membrane.
Role of the endosome
The role of the endosome is to fuse with endocytosis vesicles from the extracellular space and carry their contents to the most appropriate sub cellular region (lysosome for degradation, Golgi apparatus, etc.).
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. Mitochondrion; 10. Vacuole; 11. Cytosol; 12. Lysosome; 13. Centriole. © MesserWoland et Szczepan1990, Wikimedia, CC by-sa 3.0