Golgi apparatus processes and packages macromolecules, such as proteins and lipids, after their

synthesis and before they make their way to their destination; it is particularly important in the processing of proteins for secretion.

Found in both plant and animal cells, the Golgi is composed of stacks of membrane-bound structures known as cisternae

The cisternae stack has four functional regions: the cis-Golgi network, medial-Golgi, endo-Golgi, and trans-Golgi network

Vesicles from the endoplasmic reticulum fuse with the network and subsequently progress through the stack to the trans Golgi network, where they are packaged and sent to the required destination. Each region contains different enzymes which selectively modify the contents depending on where they reside.

The cisternae also carry structural proteins important for their maintenance as flattened membranes which stack upon each other.

The Golgi apparatus is a membrane-bound structure with a single membrane It is actually a stack of membrane-bound vesicles that are important in packaging

macromolecules for transport elsewhere in the cell. The stack of larger vesicles is surrounded by numerous smaller vesicles containing those packaged macromolecules. The enzymatic or hormonal contents of lysosomes, peroxisomes and secretory vesicles are packaged in membrane-bound vesicles at the periphery of the Golgi apparatus.

Golgi apparatus is integral in modifying, sorting, and packaging these macromolecules for cell secretion[10] (exocytosis) or use within the cell.[11] It primarily modifies proteins delivered from the rough endoplasmic reticulum but is also involved in the transport of lipids around the cell, and the creation of lysosomes.[11] In this respect it can be thought of as similar to a post office; it packages and labels items which it then sends to different parts of the cell

the vesicles that leave the rough endoplasmic reticulum are transported to the cis face of the Golgi apparatus, where they fuse with the Golgi membrane and empty their contents into the lumen.

Once inside the lumen, the molecules are modified, sorted and shipped towards their final destination. The Golgi apparatus tends to be larger and more numerous in cells that synthesise and secrete large amounts of substances, for example, the plasma B cells and the antibody-secreting cells of the immune system have prominent Golgi complexe