Possible Clues:

• United bid's huge, but has to be raised
• Belonging as a part to the whole
• Altering shapeless whole
• Inbuilt, essential
• Altering changes the whole thing
• Fundamental; function
• Learn it could hold the key to an essential part
• Whole grain? Let's be different
• Of part necessary to the completeness of a whole
• It's essential to break tin with broad back