Glycylalanine is a dipeptide of which amino acids?

The correct statements are:
$A$. Activation energy for enzyme catalysed hydrolysis of sucrose is lower than that of acid catalysed hydrolysis.
$B$. During denaturation, secondary and tertiary structures of a protein are destroyed but primary structure remains intact.
$C$. Nucleotides are joined together by phosphodiester linkage between $C_{3}$ and $C_{5}$ carbons of the pentose sugar.
$D$. Quaternary structure of proteins represents the spatial arrangement of two or more polypeptide chains.
Choose the correct answer from the options given below:

Which of the following is used in our body as a fuel for muscles and nerves and to build and repair body tissues?

The incorrect statement about denaturation of proteins is

$NH_2-CH(CH_3)-CO-NH-CH_2-COOH$
Identify the amino acids obtained by the hydrolysis of the above compound.

The protein that is a structural material is