Golgi Apparatus

The Golgi apparatus
By: Diana Dolen & Amy Wilson
10/29/2013

Today, we shall be discussing with you the Golgi apparatus and its functions. In 1897 an Italian biologist named Camillo Golgi first discovered the Golgi apparatus while investigating the nervous system. It was one of the first organelles to be discovered and observed in detail. Camillo first observed the Golgi under his microscope and termed the structure the “internal reticular apparatus.” There were many people who did not believe that Camillo had made this discovery, just dismissing it as dust on his lenses or merely an optical illusion. It wasn’t until years later when an electron microscope showed the images of the Golgi, just as Camillo had drawn them when he first observed them. The Golgi apparatus is a stack of half a dozen or so flattened, membranous sacs called cisternae. It basically looks like a stack of pancakes. The main function of the Golgi is to process, package, and deliver macromolecules, such as proteins and lipids. These macromolecules are sent to the Golgi after being built in the ER, which is the Endoplasmic reticulum, enclosed in tiny vesicles composed of membranes from the ER, so it can inspect them for flaws and discard any extra materials added during their manufacture, wraps them up and then targets them for packaging. The Golgi complex is especially active in processing proteins for secretion. The Golgi releases a special enzyme called lysosomes, which clean off any extra amino acids, and once the package is ready, it is pinched off the Golgi and released into the cytoplasm. Once the Golgi apparatus membrane buds off and forms the transport vesicle for the molecules to move to the cell membrane it then fuses and releases its contents to the outside of the cell as a secretion. Secretory vesciles that originate in the ER not only release substances outside the cell, but also provide new cell membrane. This is especially important during cell growth. Basically, the Golgi apparatus functions like an assembly line making windshields. First the windshield is formed. Once the windshield is formed it is sent down the line to be inspected for any flaws, and if one is found it is fixed. Once the windshield passes inspection, it is sent down the line to be cleaned. After the windshield is clean, it is sent down to packaging where it is wrapped up and packaged securely so it is protected during delivery. Once the windshield is delivered to the customer, it is unpackaged and ready for use.