Question

Which one is differ from the category of other three?

• A. Gastrin
• B. Glucagon
• C. Secretin
• D. Ptyalin

Answer 1

The correct option is D Ptyalin

The ptyalin is an enzyme, rest three are hormones. The saliva secreted into the oral cavity contains electrolytes ($N{a}^{+}$, $K^{+}$, $C{l}^{-}$, $HC{O}_3^{-}$) and enzymes, salivary amylase (Ptyalin) and lysozyme. The chemical process of digestion is initiated in the oral cavity by the hydrolytic action of the carbohydrate splitting enzyme, the salivary amylase (ptyalin). About 30 per cent of starch is hydrolysed here by this enzyme (optimum pH 6.8) into a disaccharide maltose. Lysozyme present in saliva acts as an antibacterial agent, that prevents infections.