The Golgi Complex Flashcards
what roles does the golgi complex play in the cell?
processing and packaging of secretory proteins, plays a role in complex polysaccharide synthesis
accepts vesicles that bud off the ER
the vesicles sent from the ER are modified and processed in the golgi complex
how is the golgi body functionally and physcially connected to the ER?
glycoproteins and membrane lipids from the ER undergo further processing and are sorted and packaged for transport
golgi complex plays a central role in membrane and protein trafficking in eukaryotic cells
what does the golgi complex consist of?
a series of membrane cisternae usually 3-8 called a GOLGI STACK
some cells have one large stack and others have hundres or thousands
how do transport vesicles come into play with the ER and golgi body?
Both ER and golgi complex are surrounded by numerous transport vesicles that carry lipids and proteins from the ER to the golgi complex and then other destinations in the cell
the golgi complex lumen is part of the endomembrane system
what are the two faces of the golgi stack?
what is the middle of the golgi stack called?
the cis-golgi network (CGN) and is oriented towards the ER
the trans-golgi network (TGN) is the opposite side of the golgi
the medial cisternae
describe the stationary cisternae model.
each cisternae in the golgi stack is a stable structure
transport of materials from one cisternae to another is mediated by shuttle vesicles
these bud off from one cisternae and fuse with the next cisternae in a cis- to trans- sequence
describe the cisternal maturation model.
the golgi cisternae are transient compartments that gradually change from CGN through medial cisternae to TGN.
transition vesicles from the ER converge to form the CGN
enzymes not needed in later compatments are returned to earlier compartments in vesicles
what is anterograde transport?
anterograde transport is the movement of material from the ER to the golgi complex toward the plasma membrane
exocytosis
what is retrograde transport?
flow of vesicles from golgi cisternae back to the ER
allows the cell to balance the flow of lipids twoard the plasma membrane
ensures supply og materials for forming new vesicles
