E.R., The golgi Body And Vesicles

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…destination of its freight with the help of carbohydrate markers, which act as labels. For example, adding the sugar mannose-6-phosphate to a protein will ensure that it is sent to a particular organelle called a lysosome. Other sugars may direct a Golgi product elsewhere, such as the cell membrane. Most targeting is not, in fact, by sugars but by "signal sequences" in the protein chain. This form of intracellular labelling is called "protein targeting".