Biomolecules
In the given pentapeptide, find out an essential amino acid $(\mathrm{Y})$ and the sequence present in the pentapeptide :
$ \text { Choose the correct answer from the options given below : } $
$ \begin{array}{|c|c|} \hline \text { (Y) } & \text { (Sequence) } \\ \hline \hline \text { Serine } & \text { Thr-Ser-Asp-Ala-Gly } \\ \hline \end{array} $
$ \begin{array}{|c|c|} \hline \text { (Y) } & \text { (Sequence) } \\ \hline \hline \text { Serine } & \text { Ser-Asp-Thr-Ala-Gly } \\ \hline \end{array} $
$ \begin{array}{|c|c|} \hline \text { (Y) } & \text { (Sequence) } \\ \hline \hline \text { Threonine } & \text { Ser-Thr-Asp-Gly-Ala } \\ \hline \end{array} $
$ \begin{array}{|c|c|} \hline \text { (Y) } & \text { (Sequence) } \\ \hline \hline \text { Threonine } & \text { Thr-Ser-Asp-Gly-Ala } \\ \hline \end{array} $
The number of possible tripeptides formed involving alanine (ala), glycine (gly) and valine (val), where no amino acid has been used more than once is:
8
3
4
6
Both human DNA and RNA are chiral molecules. The chirality in DNA and RNA arises due to the presence of
L-sugar component
D-sugar component
Chiral phosphate unit
Base unit
$ \text { Match List - I with List - II. } $
| List - I Reaction of Glucose with |
List - II Product formed |
||
|---|---|---|---|
| A. | Hydroxylamine | I. | Gluconic acid |
| B. | $\mathrm{Br}_2$ water | II. | Glucose pentacetate |
| C. | Excess acetic anhydride | III. | Saccharic acid |
| D. | Concentrated $\mathrm{HNO}_3$ | IV. | Glucoxime |
Choose the correct answer from the options given below :
A-IV, B-III, C-II, D-I
A-I, B-III, C-IV, D-II
A-III, B-I, C-IV, D-II
A-IV, B-I, C-II, D-III
Given below are two statements :
Statement I : Sucrose is dextrorotatory. However, sucrose upon hydrolysis gives a solution having mixture of products. This solution shows laevorotation.
Statement II : Hydrolysis of sucrose gives glucose and fructose. Since the laevorotation of glucose is more than the dextrorotation of fructose, the resulting solution becomes laevorotatory.
In the light of the above statements, choose the correct answer from the options given below :
Both Statement I and Statement II are false
Both Statement I and Statement II are true
Statement I is true but Statement II is false
Statement I is false but Statement II is true
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 glycosidic linkage between $\mathrm{C}_1$ and $\mathrm{C}_4$ carbons of the pentose sugar.
D. Quaternary structure of proteins represents overall folding of the polypeptide chain.
Choose the correct answer from the options given below :
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 :
C and D Only
A and D Only
C and E Only
B and E Only
The incorrect statement from the following with respect to carbohydrates is :
All monosaccharides are reducing sugars.
The monosaccharide units obtained from hydrolysis of oligosaccharides are always the same.
Starch and cellulose are typical examples of polysaccharides, which are very high molecular weight compounds of more than ten monosaccharide units.
Open chain and cyclic structures co-exist at equilibrium that are responsible for certain properties as in the case of $\mathrm{D}-(+)$-glucose.
$ \text { Match the List-I with List-II } $
| List-I Deficiency Disease |
List-I Vitamin |
||
|---|---|---|---|
| A. | Scurvy | I. | Pyridoxine |
| B. | Convulsions | II. | Vitamin A |
| C. | Cheilosis | III. | Ascorbic Acid |
| D. | Xerophthalmia | IV. | Riboflavin |
Choose the correct answer from the options given below :
A-I, B-III, C-II, D-IV
A-I, B-III, C-IV, D-II
A-III, B-I, C-IV, D-II
A-III, B-I, C-II, D-IV
$ \text { Match the List-I with List-II } $
| $ \begin{gathered} \text { List-I } \\ \text { Amino acid } \end{gathered} $ |
List-II Positive reaction/Test for functional group present in side chain of amino acid |
||
|---|---|---|---|
| A. | Glutamine | I. | Hinsberg's test |
| B. | Lysine | II. | Neutral $\mathrm{FeCl}_3$ test |
| C. | Tyrosine | III. | Ceric ammonium nitrate test |
| D. | Serine | IV. | Hoffman bromamide degradation |
Choose the correct answer from the options given below :
A-IV, B-II, C-I, D-III
A-IV, B-I, C-II, D-III
A-III, B-II, C-I, D-IV
A-IV, B-I, C-III, D-II
Identify the incorrect statement about tertiary structure of proteins.
They can be fibrous or globular in structure.
The main forces that stabilize the structure are hydrogen bonding, disulphide links, van der Waals and electrostatic forces of attraction.
The structure remains intact when exposed to pH changes.
A linear polypeptide chain will convert to a secondary structure and then further folding of the secondary structure will convert to tertiary structure.
$ \text { Given below are two statements : } $
$ \text { Statement I : } $
and
are two anomers of D-(+)-glucode.
Statement II : The open chain forms of D-glucose and D- fructose contain three similar chiral carbons at $\mathrm{C}_3, \mathrm{C}_4$ and $\mathrm{C}_5$.
In the light of the above statements, choose the correct answer from the options given below :
Both Statement I and Statement II are true
Both Statement I and Statement II are false
Statement I is true but Statement II is false
Statement I is false but Statement II is true
Identify the correct statements.
A. Glucose exists in two anomeric forms.
B. Anomers of glucose differ in configuration at $\mathrm{C}-1$ in cyclic hemiacetal structure.
C. Melting point of $\alpha$ - anomer of glucose is greater than $\beta$ - anomer.
D. Specific rotation of $\alpha$ - anomer is $+19^{\circ}$ while for $\beta$ - anomer is $+112^{\circ}$
E. $\alpha$ and $\beta$ - anomers of glucose are prepared by crystallization of saturated glucose solution at 303 K and 371 K respectively.
Choose the correct answer from the options given below :
A and B Only
B and C Only
A, B and D Only
A, B and E Only
A D-aldotetrose on oxidation with concentrated $\mathrm{HNO}_3$ resulted in optically inactive dicarboxylic acid. The structure of the D-aldotetrose is :
Given below are two statements :
Statement I : The structure of Maltose is given below:
Statement II : The structure of Lactose is given below :
In the light of the above statements, choose the correct answer from the options given below :
Both Statement I and Statement II are true
Both Statement I and Statement II are false
Statement I is true but Statement II is false
Statement I is false but Statement II is true
Match the List-I with List-II
| List-I Name of amino acid | List-II One letter symbol/type |
|---|---|
| A. Arginine | I. D/Non-essential |
| B. Aspartic acid | II. R/Essential |
| C. Lysine | III. E/Non-essential |
| D. Glutamic acid | IV. K/Essential |
Choose the correct answer from the options given below :
A-II, B-I, C-IV, D-III
A-IV, B-III, C-II, D-I
A-III, B-IV, C-I, D-II
A-II, B-IV, C-I, D-III
Identify the correct pair having amino acid (A) and the hormone (B) that is iodinated derivative of the amino acid (A).
(T and Y represent one letter code for amino acids)
Amino acid (A) - T Hormone (B) - Insulin
Amino acid (A) - T Hormone (B) - Thyroxine
Amino acid (A) - Y Hormone (B) - Thyroxine
Amino acid (A) - Y Hormone (B) - Insulin
Match List - I with List - II.
| List - I Vitamin |
List - II Name |
||
|---|---|---|---|
| A | Vitamin B1 | I | Pyridoxine |
| B | Vitamin B2 | II | Ascorbic acid |
| C | Vitamin B6 | III | Thiamine |
| D | Vitamin C | IV | Riboflavin |
Choose the correct answer from the options given below:
A-II, B-I, C-III, D-IV
A-IV, B-III, C-II, D-I
A-III, B-IV, C-I, D-II
A-I, B-III, C-II, D-IV
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 :
Statement I is incorrect but Statement II is correct
Both Statement I and Statement II are incorrect
Both Statement I and Statement II are correct
Statement I is correct but Statement II is incorrect
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 :
Identify the pair of reactants that upon reaction, with elimination of HCl will give rise to the dipeptide Gly-Ala.
Fat soluble vitamins are:
A. Vitamin $\mathrm{B}_1$
B. Vitamin C
C. Vitamin E
D. Vitamin B 12
E. Vitamin K
Choose the correct answer from the options given below:
$ \text { Which of the following is the correct structure of L-Fructose? } $
Identify the correct statement among the following :
Identify the essential amino acids from below:
(A) Valine
(B) Proline
(C) Lysine
(D) Threonine
(E) Tyrosine
Choose the correct answer from the options given below:
(A), (C) and (D) only
(C), (D) and (E) only
(A), (C) and (E) only
(B), (C) and (E) only
Match List - I with List - II.
| List - I (Carbohydrate) | List - II (Linkage Source) |
|---|---|
| (A) Amylose | (I) $\beta$ - $C_1 - C_4$, plant |
| (B) Cellulose | (II) $\alpha$ - $C_1 - C_4$, animal |
| (C) Glycogen | (III) $\alpha$ - $C_1 - C_4$, $\alpha$ - $C_1 - C_6$, plant |
| (D) Amylopectin | (IV) $\alpha$ - $C_1 - C_4$, plant |
Choose the correct answer from the options given below :
(A)-(II), (B)-(III), (C)-(I), (D)-(IV)
(A)-(III), (B)-(III), (C)-(I), (D)-(IV)
(A)-(IV), (B)-(I), (C)-(III), (D)-(II)
(A)-(IV), (B)-(I), (C)-(II), (D)-(III)
Match List-I with List-II.
| List - I (Saccharides) | List - II (Glycosidic-linkages found) |
|---|---|
| (A) Sucrose | (I) α 1 $-$ 4 |
| (B) Maltose | (II) α 1 $-$ 4 and α 1 $-$ 6 |
| (C) Lactose | (III) α 1 $-$ β 2 |
| (D) Amylopectin | (IV) β 1 $-$ 4 |
Choose the correct answer from the options given below :
(A)-(III), (B)-(I), (C)-(IV), (D)-(II)
(A)-(I), (B)-(II), (C)-(III), (D)-(IV)
(A)-(II), (B)-(IV), (C)-(III), (D)-(I)
(A)-(IV), (B)-(II), (C)-(I), (D)-(III)
Identify correct conversion during acidic hydrolysis from the following :
(A) starch gives galactose.
(B) cane sugar gives equal amount of glucose and fructose.
(C) milk sugar gives glucose and galactose.
(D) amylopectin gives glucose and fructose.
(E) amylose gives only glucose.
Choose the correct answer from the options given below :
(A), (B) and (C) only
(B), (C) and (D) only
(B), (C) and (E) only
(C), (D) and (E) only
Given below are two statements:
Statement I : D-glucose pentaacetate reacts with 2,4 -dinitrophenylhydrazine
Statement II : Starch, on heating with concentrated sulfuric acid at $100^{\circ} \mathrm{C}$ and $2-3 \mathrm{atmosphere}$ pressure produces glucose.
In the light of the above statements, choose the correct answer from the options given below
Match List - I with List - II.
| List - I | List - II | ||
|---|---|---|---|
| (A) | Adenine | (I) | ![]() |
| (B) | Cytosine | (II) | ![]() |
| (C) | Thymine | (III) | ![]() |
| (D) | Uracil | (IV) | ![]() |
Choose the correct answer from the options given below :
The carbohydrate "Ribose" present in DNA, is
A. A pentose sugar
B. present in pyranose from
C. in "D" configuration
D. a reducing sugar, when free
E. in $\propto$-anomeric form
Choose the correct answer from the options given below:
The $\alpha$-Helix and $\beta$ - Pleated sheet structures of protein are associated with its :
Given below are two statements:
Statement I: Fructose does not contain an aldehydic group but still reduces Tollen's reagent
Statement II: In the presence of base, fructose undergoes rearrangement to give glucose.
In the light of the above statements, choose the correct answer from the options given below
Identify the number of structure/s from the following which can be corelated to D-glyceraldehyde.

Which of the following acids is a vitamin ?
The total number of hydrogen bonds of a DNA-double Helix strand whose one strand has the following sequence of bases is ________.
$5^{\prime}-\mathrm{G}-\mathrm{G}-\mathrm{C}-\mathrm{A}-\mathrm{A}-\mathrm{A}-\mathrm{T}-\mathrm{C}-\mathrm{G}-\mathrm{G}-\mathrm{C}-\mathrm{T}-\mathrm{A}-3^{\prime}$
Explanation:
Two nucleic acid chains are wound about each other and held together by H bonds between pair of bases.
Adenine from two hydrogen bonds with thymine and Guanine form three hydrogen bond with cytosine.
$5^{\prime} \mathrm{G}-\mathrm{G}-\mathrm{C}-\mathrm{A}-\mathrm{A}-\mathrm{A}-\mathrm{T}-\mathrm{C}-\mathrm{G}-\mathrm{G}-\mathrm{C}-\mathrm{T}-\mathrm{A}-3^{\prime}$
In given DNA strand total seven guanine and cytosine bases which form total 21 H -bonds and six adenine and thymine base which will form total 12 H -bonds with other DNA strand.
Total no. of H bonds $=7 \times 3+6 \times 2=33$
Ans. 33
The incorrect statement about Glucose is :
The $\mathrm{F}^{-}$ ions make the enamel on teeth much harder by converting hydroxyapatite (the enamel on the surface of teeth) into much harder fluoroapatite having the formula.

The incorrect statement regarding the given structure is
The incorrect statements regarding enzymes are :
(A) Enzymes are biocatalysts.
(B) Enzymes are non-specific and can catalyse different kinds of reactions.
(C) Most Enzymes are globular proteins.
(D) Enzyme - oxidase catalyses the hydrolysis of maltose into glucose.
Choose the correct answer from the option given below :
DNA molecule contains 4 bases whose structure are shown below. One of the structures is not correct, identify the incorrect base structure.
Coagulation of egg, on heating is because of :
Which of the following gives a positive test with ninhydrin ?
Match List I with List II
| LIST I | LIST II | ||
|---|---|---|---|
| A. | $\alpha$ - Glucose and $\alpha$ - Galactose | I. | Functional isomers |
| B. | $ \alpha \text { - Glucose and } \beta \text { - Glucose } $ |
II. | Homologous |
| C. | $ \alpha \text { - Glucose and } \alpha \text { - Fructose } $ |
III. | Anomers |
| D. | $ \alpha \text { - Glucose and } \alpha \text { - Ribose } $ |
IV. | Epimers |
Choose the correct answer from the options given below:
Which of the following is the correct structure of L-Glucose?
Match List I with List II
| List - I | List - II | ||
|---|---|---|---|
| (A) | Glucose/$\mathrm{NaHCO_3/\Delta}$ | (I) | Gluconic acid |
| (B) | $\text { Glucose } / \mathrm{HNO}_3$ | (II) | No reaction |
| (C) | $\text { Glucose } / \mathrm{HI} / \Delta$ | (III) | n-hexane |
| (D) | Glucose/Bromine water | (IV) | Saccharic acid |
Choose the correct answer from the options given below:






















