Not quite. Say you have a big bowl of macaroni. Your body can only use a small percentage of the protein present.
Now you make a béchamel sauce (scalded milk, butter and flour) and melt in some cheese to make macaroni and cheese.
Besides using the protein in the milk and cheese, the gaps in the amino acid profile of the pasta is filled in and it's all usable.
"To give anything less than your best is to sacrifice the Gift."