Golgi apparatus
The Golgi apparatus receives proteins and lipids from the ER, finishes them, and sorts them into vesicles for delivery. Cargo goes to the cell membrane, to lysosomes, or out of the cell: think of a mail room that modifies, labels, addresses, and ships.
- 1NucleusOrganelle · double membrane
- 2MitochondrionOrganelle · double membrane
- 3RibosomeMolecular machine · no membrane
- 4Endoplasmic reticulumOrganelle · single membrane network
- 5Golgi apparatusOrganelle · single membrane stacks
- 6LysosomeOrganelle · single membrane
- 7Cell membraneBoundary · phospholipid bilayer
- 8CentriolesMicrotubule pair · organizes the spindle
Animal cell: what you are looking at
A flexible, roughly rounded cell 10–30 µm across, bounded only by its membrane. It has a pair of centrioles near the nucleus and many lysosomes, but no wall, no chloroplasts, and no large central vacuole.
Centrioles. A pair of short microtubule cylinders at right angles; they organize the spindle during cell division.
The golgi apparatus is outlined in coral; it occurs in animal cells, plant cells, fungi, protists. Hover or tab through the key to light up the other structures, and click any of them to open its page.
Compare all eight organelles ↗Know its structure
| Found in | Animal cells, Plant cells, Fungi, Protists |
| Membranes | One membrane per cisterna; a stack usually holds 4–8 flattened cisternae |
| Typical size | Each cisterna is about 1 µm across; a stack is roughly 0.5–2 µm thick |
| Number per cell | One ribbon of linked stacks near the nucleus in animal cells; dozens to hundreds of separate stacks (dictyosomes) in plant cells |
| Structure | A cis face receives vesicles from the ER, medial cisternae modify the cargo, and the trans face buds off vesicles for delivery |
| Discovered | Stained and described by Camillo Golgi in 1898; dismissed as an artifact by many until electron microscopy confirmed it in the 1950s |
What it does
- Modifies proteins and lipids. Trims and rebuilds sugar chains, and adds sulfate or phosphate groups as cargo moves from cis to trans
- Sorts and ships. Tags lysosomal enzymes with mannose-6-phosphate and packs secreted proteins into vesicles headed for the cell membrane
- Builds plant cell-wall polysaccharides. Makes the pectins and hemicelluloses of the wall (cellulose itself is made at the cell membrane)
- Seeds lysosomes. Vesicles that bud from the trans face mature into lysosomes
Golgi apparatus: common questions
Wondering about the why? Start here.
What does the Golgi apparatus do?
The Golgi receives proteins and lipids from the ER, finishes them, and sorts them for delivery. Cargo enters at the cis face, moves through a stack of 4 to 8 flattened cisternae where enzymes rebuild its sugar chains and add sulfate or phosphate groups, and leaves from the trans face in vesicles bound for the cell membrane, lysosomes, or secretion. The mucus that lines your gut is up to 80% sugar by mass, nearly all of it attached in the Golgi.
Read: cell transportHow does the Golgi know where to send a protein?
It reads molecular address tags. Lysosomal enzymes get a mannose-6-phosphate group that a receptor in the trans Golgi recognizes and diverts into lysosome-bound vesicles; proteins without a tag follow the default route to the cell surface. In I-cell disease the tagging enzyme is missing, so the digestive enzymes are secreted out of the cell and undigested material piles up inside.
See where tagged enzymes end upIs the Golgi apparatus in plant cells?
Yes. Animal cells usually have one ribbon of linked stacks near the nucleus, but plant cells contain dozens to hundreds of separate stacks called dictyosomes. Besides finishing proteins, the plant Golgi builds the pectins and hemicelluloses of the cell wall and ships them out in vesicles; cellulose itself is spun by enzyme complexes in the cell membrane.
Go back a step to the ER