In a cell protein synthesis is the primary function of

In a cell, protein synthesis  is the primary function of the ribosomes, found in both eukaryotic and prokaryotic cells.

A Ribosome is a cell organelle that makes protein. The location of the ribosome  in a cell determine the kind of protein it makes.  If the ribosome is attached to the endoplasmic reticulum, the proteins made are utilized both  within and outside the cell. If the ribosome is in the cytoplasm, floating freely, then the kind of protein made will be utilized within the cell only.

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