Answer
The main difference between ER bound ribosomes and free ribosomes in the cytosol is that the proteins made by each respective type of ribosomes end up in different cellular or extra-cellular locations.
Work Step by Step
ER bound ribosomes synthesize proteins that will either be incorporated into cell membranes or lysosomes or those that will be exported out of the cell, while free ribosomes in cytosol roles make proteins that function in the cytosol or those that are imported into mitochondria and some other organelles.
