Nitrogen is necessary for the formation of proteins because it is a key component of amino acids. Other biological molecules like fats, starch, and sugars do not contain nitrogen. Therefore, nitrogen is specifically needed to form proteins.
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Nitrogen is essential for the formation of proteins because it is a critical component of amino acids. Other biological molecules, such as fats, starch, and sugar, do not contain nitrogen. Thus, the correct answer to the question is that nitrogen is needed to form proteins. ;