Amino acids are the building blocks of proteins. Another way of thinking of this is to compare amino acids to the beads of a necklace. Without the string to hold them together, they are just beads. The amino acids in formula are different from amino acids in food because they are already broken down. Because they are already separated from each other, they are absorbed quickly and all at once, giving the body a small amount of time to use them.
A protein is a chain of amino acids connected together. You can think of this like a beaded necklace. The beads (amino acids) are connected together by a string (bond), which forms a long chain (protein). Therefore, a protein is “intact” or “whole.”
Proteins are connected together; free amino acids are not.