Why is it important that antibodies have a symmetrical quaternary structure? to enable binding to many different antigens to create a variable region to create two identical binding sites for antigens to ensure a stable structure?

It is important that antibodies have a symmetrical quaternary structure to create two identical binding sites for antigens. An antibody is a relatively large protein having a Y-shape. Plasma cells produce antibodies which are then used by the immune system to fight off pathogens (e.g. bacteria and virus). The antibody is able to recognize the antigen of the pathogen. It binds with it either to neutralize it directly or “tag” the microbe for future attack by other parts of the immune system. 

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