Proteins that are synthesized in ribosomal subunits undergo extensive post-translational modification and are packaged and directed to the appropriate destination. which structural component of a cell is involved in such modification?

Golgi apparatus is the organelle that is involved in the post-translational modification of the proteins and packaging of these proteins in vesicles for transportation to their appropriate destination.

Golgi apparatus is having two faces initial face is entry face(cis face) from where unprocessed protein from ER enters and trans face(maturing face) from where the matured processed proteins are released into the vesicles.

The modification that takes place in the Golgi apparatus by Golgi enzymes are glycosylation, sulfation, and phosphorylation. Then these proteins are extruded from trans face of Golgi apparatus in the form of vesicle which have information about its destination in the cell.

Therefore Golgi apparatus is the structural component of a cell involved in such modification.

enzyme active site and substrate specificity

enzymes bind with chemical reactants called substrates. there may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. in some reactions, a single-reactant substrate is broken down into multiple products