Biomolecules — JEE Advanced PYQs

A known artificial sweetener X is composed of 4-chloro-4-deoxy-α-D-galactose and 1,6-dichloro-1,6-dideoxy-β-D-fructose joined by a glycosidic linkage. Structure of D-galactose is given below:

The correct structure of $\mathbf{X}$ is:

The correct statement(s) regarding sugars is (are)

Given: Specific rotations of L-(-)-glucose and L-(+)-fructose are -52.5° and +92.5°, respectively.

Match the compounds in List-I with the appropriate observations in List-II and choose the correct option.

List-I
(P) (see structure)
(Q) (see structure)
(R) (see structure)
(S) (see structure)

List-II
(1) Reaction with phenyl diazonium salt gives yellow dye.
(2) Reaction with n …

A linear octasaccharide (molar mass $=1024\mathrm{g}{\mathrm{mol}}^{-1}$) on complete hydrolysis produces three monosaccharides: ribose, 2-deoxyribose and glucose. The amount of 2-deoxyribose formed is $58.26\%(\mathrm{w}/\mathrm{w})$ of the total amount of the monosaccharid …

Aspartame, an artificial sweetener, is a dipeptide aspartyl phenylalanine methyl ester. The structure of aspartame is

For a double strand DNA, one strand is given below:

The amount of energy required to split the double strand DNA into two single strands is ____ $\mathrm{kcal}{\mathrm{mol}}^{-1}$.
[Given : Average energy per H-bond for A-T base pair $=1.0\mathrm{kcal}{\mathrm{mol}}^{-1}$, G- …

A disaccharide X cannot be oxidised by bromine water. The acid hydrolysis of X leads to a laevorotatory solution. The disaccharide $\mathbf{X}$ is

Treatment of D-glucose with aqueous NaOH results in a mixture of monosaccharides, which are

Given

D-Glucose
The compound(s), which on reaction with ${\mathrm{HNO}}_3$ will give the product having degree of rotation, $[\alpha {]}_{\mathrm{D}}=-52.7^{\circ }$ is (are)

The structure of a peptide is given below

If the absolute values of the net charge of the peptide at $\mathrm{pH}=2,\mathrm{pH}=6$, and $\mathrm{pH}=11$ are $\left|{\mathrm{z}}_1\right|,\left|{\mathrm{z}}_2\right|$ and $\left|z_3\right|$, respectively, then what is …

The Fischer projection of D-erythrose is shown below.

D-Erythrose and its isomers are listed as P, Q, R, and S in Column-I. Choose the correct relationship of P, Q, R, and S with D-erythrose from Column II.
| Q. | (see structure …

Which of the following statement(s) is(are) true ?

The Fischer presentation of D-glucose is given below.

The correct structure(s) of $\beta$-L-glucopyranose is (are)

For 'invert sugar', the correct statement(s) is(are)
(Given: specific rotations of (+)-sucrose, (+)-maltose, L-(-)-glucose and L-(+)-fructose in aqueous solution are $+66^{\circ },+140^{\circ },-52^{\circ }$ and $+92^{\circ }$, respectively)

Treatment of compound O with ${\mathrm{KMnO}}_4/{\mathrm{H}}^{+}$ gave P, which on heating with ammonia gave Q. The compound Q on treatment with ${\mathrm{Br}}_2/\mathrm{NaOH}$ produced R. On strong heating, Q gave S, which on further treatment with ethyl 2-bromopropanoate in t …

The structure of D-(+)-glucose is
[C@H](O)[C@H](O)[C@H](O)CO</smiles>](cdn-74c395fe671eeb76258f9253)
The structure of L-(-)-glucose is

The total number of distinct naturally occurring amino acids obtained by complete acidic hydrolysis of the peptide shown below is

A tetrapeptide has -COOH group on alanine. This produces glycine (Gly), valine (Val), phenyl alanine (Phe) and alanine (Ala), on complete hydrolysis. For this tetrapeptide, the number of possible sequences (primary structures) with $-N{H}_2$ group attached to a chiral center is

The substituents ${\mathbf{R}}_1$ and ${\mathbf{R}}_2$ for nine peptides are listed in the table given below. How many of these peptides are positively charged at $\mathrm{pH}=7.0$ ?
| Peptide | ${\mathrm{R}}_1$ | ${\mathrm{R}}_2$ || --- | --- | --- …

When the following aldohexose exists in its D-configuration, the total number of stereoisomers in its pyranose form is

The following carbohydrate is

A decapeptide (Mol. Wt. 796) on complete hydrolysis gives glycine (Mol. Wt. 75), alanine and phenylalanine. Glycine contributes 47.0 % to the total weight of the hydrolysed products. The number of glycine units present in the decapeptide is

The correct statement about the following disaccharide is

The total number of basic groups in the following form of lysine is

(see structure)

The correct statement(s) about the following sugars $\mathbf{X}$ and $\mathbf{Y}$ is(are)

Cellulose upon acetylation with excess acetic anhydride/${\mathrm{H}}_2{\mathrm{SO}}_4$ (catalytic) gives cellulose triacetate whose structure is