The Golgi (GOL-JEE) apparatus is often called the “cell’s post office.” It is an organelle with the main job of modifying, sorting and packaging the proteins that the endoplasmic reticulum sends to it.
If you think about it, this is the same type of job that happens in the local post office. Also called just “Golgi”, it will either send proteins off to be sent somewhere else or it will store them.
If you look at the Golgi under an intense microscope, you will see that they appear like a stack of pancakes. These are actually stacked membranes with ribosomes often found in between the membranes.
Both animal and plant cells have Golgi’s and when they get molecules such as proteins from the endoplasmic reticulum, the Golgi expands to make it larger.
When the ER sends simple proteins to the Golgi it will modify or change the proteins to match the needs of the organism. Once that job is done, it will package these new proteins in a vesicle that is new or in a lysosome.
Now it sends instructions to the vesicle as to where the new proteins need to be delivered. The cell makes use of some of the proteins by releasing them to various organism parts, and stores others for use at a later time.
The endoplasmic reticulum and the Golgi work closely together to achieve their jobs.
It’s not surprising that they are located next to each other. Since the Golgi also has to work with vesicles, they are found surrounding it.
There are three types of vesicles that work with the ER and the Golgi: Bringing proteins from the ER are the transport vesicles. Secretory vesicles then move proteins out (occasionally as lysosomes).
Exocytotic vesicles focus on moving proteins that are needed in spaces that are called “extracellular”. They do this by blending with the membrane and then releasing their contents.
It’s important to note that in mammals, the Golgi is often very close to the nucleus. However, this is not found in plant cells, where they don’t have any particular location.
Some scientists believe that there are Golgi stacks that differentiate and have a variety of enzyme collections. This may explain the processing of the cargo to protein from the ER and then movement out.
As with many things in science, Golgi apparatus is named after the biologist that discovered it in 1897. In this case it is Camillo Golgi, an Italian biologist.
It has to be remembered that during that time, microscopes were very limited and there was little detail of a cell that could be seen.
Because of this, many scientists of the era rejected Golgi’s discovery. Over 50 years later the invention of the more powerful electron microscope proved that Golgi was correct.
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