Identify the correct statements.

A. Arginine and Tryptophan are essential amino acids.

B. Histidine does not contain heterocyclic ring in its structure.

C. Proline is a six membered cyclic ring amino acid.

D. Glycine does not have chiral centre.

E. Cysteine has characteristic feature of side chain as $\mathrm{MeS}-\mathrm{CH}_2-\mathrm{CH}_2-$.

Choose the correct answer from the options given below :

Given below are two statements :

Statement (I) : On hydrolysis, oligo peptides give rise to fewer number of α-amino acids while proteins give rise to a large number of β-amino acids.

Statement (II) : Natural proteins are denatured by acids which convert the water soluble form of fibrous proteins to their water insoluble form.

In the light of the above statements, choose the most appropriate answer from the options given below :

Given below are two statements:

Statement I: D-(+)-glucose + D-(+) fructose $\xrightarrow{-\mathrm{H}_2 \mathrm{O}}$ Sucrose

$$\text { sucrose } \xrightarrow{\text { hydrolysis }} \mathrm{D}-(+) \text { glucose }+\mathrm{D}-(+) \text { fructose }$$

Statement II: Invert sugar is formed during sucrose hydrolysis

In the light of the above statements, choose the correct answer from the options given below

A dipeptide, " $x$ " on complete hydrolysis gives " $y$ " and " $z$ ". " $y$ " on treatment with aq. $\mathrm{HNO}_2$ produces lactic acid. On the other hand " z " on heating gives the following cyclic molecule.

Based on the information given, the dipeptide $X$ is :