Golgi apparatus definition, structure, functions and diagram 2.3.3 identify structures from electron micrographs of liver cells
The Golgi apparatus is an organelle found in most cells.Before the vesicles are sent to their destination, part of the endomembrane system in the cytoplasm packages the proteins into them.The intersection of the secretory, lysosomal, and endocytic pathways is where it resides.It is important for the processing of proteins for secretion because it contains a set of sugars that attach to them as they move through the apparatus.
The Italian scientist named it after him in 1898.[3]
The Golgi apparatus was discovered and observed in detail due to its large size and distinctive structure.It was discovered in 1898 by an Italian physician.He described the structure as apparato reticolare interno after observing it under his microscope.The appearance of the structure was thought to be an optical illusion by some people.The discovery was confirmed with the development of modern microscopes.The Golgi apparatus was referred to by various names, including the "Golgi–Holmgren apparatus".The term "Golgi apparatus" was first used in the scientific literature in 1913, while the other term was introduced in 1956.[3]
The Golgi apparatus is subcellular in nature.A Golgi apparatus is usually located near the cell nucleus in mammals.The stacks are linked by tubular connections.The Golgi apparatus has tubular connections.The Golgi apparatuses lose their mutual connections when they are depolymerized.In Saccharomyces cerevisiae, Golgi apparatuses are scattered throughout the cytoplasm.Golgi stacks are not concentrated at the centrosomal region in plants.The organization of the plant depends on actin cables.Golgi are adjacent to ER exit sites.[7]
The Golgi apparatus is made up of a series of compartments and is a collection of disks called cisternae.40 to 100 stacks of cisternae can be found in a mammal cell.Some protists have seen as many as sixty cisternae in a stack.The cis Golgi network (CGN) is one of the main networks of this collection of cisternae.The first cisternal structure is the CGN, followed by the TGN and finally the cell surface.The TGN can be separated from the stack.In yeast and plants, the TGN may act as an early endosome.[6]
Structural and organizational differences exist in the Golgi apparatus.Golgi stacking is not observed in some yeasts.Saccharomyces cerevisiae does not have stacked Golgi.Plants have individual stacks of the Golgi apparatus.[6]
The Golgi apparatus is larger and more numerous in cells that produce large amounts of substances.
Each cisternal stack has a cis entry face and a trans exit face.The faces are characterized by their unique features.There are different types of enzymes responsible for modifying the cargo.The fate of the protein is influenced by these modifications.The Golgi apparatus can be split into two parts, the cis face cisternae and the trans face.It was 5 and 10.
The Golgi apparatus is a major collection and dispatch station.The Golgi apparatus is involved in the fusion of the ER and vesicles.These cargo proteins can be used in the cell or for exocytosis.The Golgi is similar to a post office in that it packages and labels items which it sends to different parts of the cell.The Golgi apparatus is involved in lysosome formation.[2]
The function and structure of the Golgi apparatus are interdependent.The individual stacks allow for progressive processing of cargo proteins as they travel from the cisternae to the trans Golgi face.The Golgi stacks have enzymatic reactions only near its membrane surfaces.This feature is different to the ER, which has amylases in its lumen.There is a lot of post-translational modification going on.The early CGN has the occurrence of thephosphorylation of oligosaccharides on lysosomal proteins.The removal of mannose residues is associated with Cis cisterna.There is removal of mannose and addition of N-acetylglucosamine.The trans cisternae contains galactose and sialic acid.The TGN is home to the lysis of tyrosines and carbohydrates.The addition of glycosylation andphosphorylation is one of the general post-translational modifications of proteins.There is a signal sequence that determines the final destination.The Golgi apparatus adds a mannose-7-phosphate label to the lysosomes.The formation of proteoglycans is an important function of the Golgi apparatus.Proteoglycans are created in the Golgi by the creation of proteins.There are long unbranched polysaccharides present in the matrix of animals.
The cis face of the Golgi apparatus is where the vesicles that leave the rough reticulum are taken.The modified molecules are sorted for transport to their next destinations.
The trans-Golgi network (TGN) is a complex network of membranes and associated vesicles that are moved through the Golgi cisternae towards the trans face.This area of the Golgi is where proteins are sorted and shipped to their destinations by their placement into one of at least three different types of vesicles.