Assertion (A) : All the proteins in our food are digested in small intestine only. Reason (R) : The Protein-digesting enzymes from pancreas are released into small intestine.

Assertion is false because protein digestion begins in the stomach: gastric glands secrete hydrochloric acid and pepsin, which initiate proteolysis by converting proteins into peptides within the stomach lumen [1]. Reason is true — the pancreas secretes pancreatic juice containing proteases (trypsin, chymotrypsin, carboxypeptidases) that are released into the duodenum/small intestine where they perform the bulk of peptide cleavage; many pancreatic enzymes are secreted as zymogens and activated in the intestinal lumen [2]. Thus R is true but it does not make A correct, since some protein digestion occurs in the stomach before pancreatic action in the small intestine.

Sources

1. [1] Science , class X (NCERT 2025 ed.) > Chapter 5: Life Processes > Activity 5.3 > p. 85
2. [2] https://naspghan.org/files/documents/pdfs/training/curriculum-resources/physiology-series/Protein_Digestion_NASPGHAN.pdf