Concept:Proteins are defined by their well-defined three-dimensional conformation and biological function, not solely by their length.
Explanation:The Assertion states that insulin is a protein but glycyl alanine is not.
This is correct because insulin is a polypeptide hormone made of
51 amino acids.
Insulin folds into a precise, stable three-dimensional structure that is essential for its biological activity.
Hence, it is correctly classified as a protein despite having fewer than
100 residues.
Glycyl alanine is simply a dipeptide formed from two amino acids (glycine and alanine).
It lacks the necessary chain length to fold into a stable, protein-like conformation.
Therefore, it does not meet the structural criteria to be called a protein.
The Reason provides the general biochemical rule: a polypeptide with fewer than
100 residues qualifies as a protein if it has a well-defined conformation.
This rule directly explains why insulin (
51 residues, well-defined conformation) is a protein, while glycyl alanine (
2 residues, no such conformation) is not.
Thus, the Reason correctly explains the Assertion.
Answer:Option C: Both Assertion and Reason are correct.