Amide group is present in

Total number of essential amino acids among the given list of amino acids is . . . .
Arginine,Phenylalanine,Aspartic acid,Cysteine,Histidine,Valine,Proline

Which property of glycine distinguishes it from other naturally occurring amino acids?

Which of the following is a molecular disease?

Optically inactive amino acid is :-

Assertion $(A)$: The denaturation of proteins can destroy all $1^{\circ}, 2^{\circ}$ and $3^{\circ}$ protein structures.
Reason $(R)$: Curdling of milk is due to denaturation of proteins.
The correct option among the following is