Golgi apparatus
Say it: GOHL-jee ap-uh-RAT-us
The Golgi apparatus is a stack of flattened membrane sacs that modifies, sorts and packages proteins and lipids sent from the endoplasmic reticulum.
Also: Golgi body, Golgi complex, Golgi, dictyosome
Definition
What is the Golgi apparatus?
The Golgi apparatus is an organelle of eukaryotic cells made of a stack of flattened, membrane-bound sacs called cisternae, usually lying close to the nucleus. It acts as the cell's processing and shipping center for proteins and lipids that arrive from the endoplasmic reticulum (ER).
Transport vesicles from the ER fuse with the cis face, the side of the stack nearest the ER. As molecules move through the stack, enzymes modify them, most often by adding or trimming sugar chains to make glycoproteins, and attach chemical tags, such as phosphate groups, that mark where each one should go. At the opposite side, the trans face, the finished products are packed into new vesicles headed for lysosomes, for the plasma membrane, or for release outside the cell.
Cells that secrete a great deal, such as those making digestive enzymes or hormones, have large and numerous Golgi stacks. In plant cells, the Golgi also makes polysaccharides for the cell wall. The organelle is named after the Italian scientist Camillo Golgi, who described it in 1898.
Practice it
Where you'll meet it
Related
Terms that go with it
- Endoplasmic reticulumThe endoplasmic reticulum is a network of membrane sacs and tubes in eukaryotic cells that makes and processes proteins and lipids.
- LysosomeA lysosome is a membrane-bound organelle filled with acidic digestive enzymes that break down worn-out cell parts, food particles and microbes.
- OrganelleAn organelle is a specialized structure inside a cell, usually wrapped in its own membrane, that carries out a particular job for the cell.
- Post-translational modificationA post-translational modification is a chemical change made to a protein after it is built on the ribosome, often altering its activity or location.
- ProteinA protein is a large molecule made of one or more chains of amino acids, folded into a specific shape that determines its job in the body.
- Cell membraneThe cell membrane is the thin, flexible boundary of lipids and proteins that encloses every cell and controls what enters and leaves it.
Sources
Checked against
Written for biofideX in plain words, after checking these references:
- OpenStax Biology 2e, 4.4 The Endomembrane System and Proteins
- NHGRI Talking Glossary: Golgi Body
- MeSH (NLM): Golgi Apparatus
Last updated
Spotted a mistake? Tell us and we'll correct it.
Practice Cell Biology
Free cell biology quizzes, with an explanation for every answer.
See the Quizzes