Biomolecules
200 Questions
Start JEE Mains Test
2022
Q101
JEE Mains
MCQ
14 Mar 2026
L-isomer of a compound 'A' (C4H8O4) gives a positive test with [Ag(NH3)2]+. Treatment of 'A' with acetic anhydride yields triacetate derivative. Compound 'A' produces an optically active compound (B) and an optically inactive compound (C) on treatment with bromine water and HNO3 respectively. Compound (A) is :
A.
B.
C.
D.
2022
Q102
JEE Mains
MCQ
14 Mar 2026
Match List-I with List-II
| List - I Enzyne |
List - II Conversion of |
||
|---|---|---|---|
| A. | Invertase | I. | Starch into maltose |
| B. | Zymase | II. | Maltose into glucose |
| C. | Diastase | III. | Glucose into ethanol |
| D. | Maltase | IV. | Cane sugar into glucose |
Choose the most appropriate answer from the options given below :
A.
A-III, B-IV, C-II, D-I
B.
A-III, B-II, C-I, D-IV
C.
A-IV, B-III, C-I, D-II
D.
A-IV, B-II, C-III, D-I
2022
Q103
JEE Mains
MCQ
14 Mar 2026
Which one of the following is a water soluble vitamin, that is not excreted easily?
A.
Vitamin B2
B.
Vitamin B1
C.
Vitamin B6
D.
Vitamin B12
2022
Q104
JEE Mains
MCQ
14 Mar 2026
A polysaccharide 'X' on boiling with dil H2SO4 at 393 K under 2-3 atm pressure yields 'Y'. 'Y' on treatment with bromine water gives gluconic acid. 'X' contains $\beta$-glycosidic linkages only. Compound 'X' is :
A.
starch
B.
cellulose
C.
amylose
D.
amylopectin
2022
Q105
JEE Mains
Numerical
14 Mar 2026
In a linear tetrapeptide (Constituted with different amino acids), (number of amino acids) $-$ (number of peptide bonds) is ________.
Correct Answer: 1
Explanation:
In tetrapeptide
No. of amino acids = 4
No. of peptide bonds = 3
Hence, (1)
No. of amino acids = 4
No. of peptide bonds = 3
Hence, (1)
2022
Q106
JEE Mains
Numerical
14 Mar 2026
C6H12O6 $\buildrel \text{Zymase} \over \longrightarrow $ A $\mathrel{\mathop{\kern0pt\longrightarrow} \limits_\Delta ^\text{NaOI}} $ B + CHI3
The number of carbon atoms present in the product B is _______________.
Correct Answer: 1
Explanation:
$\mathrm{C}_6 \mathrm{H}_{12} \mathrm{O}_6 \stackrel{\text { Zymase }}{\longrightarrow} \mathrm{C}_2 \mathrm{H}_5 \mathrm{OH} \stackrel{\mathrm{NaOl}}{\longrightarrow} \underset{\text { (B) }}{\mathrm{HCOONa}}+\mathrm{CHI}_3
$
2022
Q107
JEE Mains
Numerical
14 Mar 2026
The number of oxygens present in a nucleotide formed from a base, that is present only in RNA is ___________.
Correct Answer: 9
Explanation:
Uracil is the base which only present is RNA.
Structure of nucleotides number of 0-9.
Structure of nucleotides number of 0-9.
2022
Q108
JEE Mains
Numerical
14 Mar 2026
How many of the given compounds will give a positive Biuret test ____________ ?
Glycine, Glycylalanine, Tripeptide, Biuret
Correct Answer: 2
Explanation:
Since dipeptides and free amino acids do not give
biuret test. Hence glycine and glycylalanine do not
give this test.
2022
Q109
JEE Mains
Numerical
14 Mar 2026
In alanylglycyl leucyl alanyl valine, the number of peptide linkages is ___________.
Correct Answer: 4
Explanation:
The given pentapeptide is
$\text { ALA - GLY - LEU - ALA - VAL }$
It has 4 peptide linkages.
$\text { ALA - GLY - LEU - ALA - VAL }$
It has 4 peptide linkages.
2021
Q110
JEE Mains
MCQ
14 Mar 2026
Which of the following is not an example of fibrous protein?
A.
Keratin
B.
Albumin
C.
Collagen
D.
Myosin
2021
Q111
JEE Mains
MCQ
14 Mar 2026
Which one of the following compounds contains $\beta$-C1-C4 glycosidic linkage?
A.
Lactose
B.
Sucrose
C.
Maltose
D.
Amylose
2021
Q112
JEE Mains
MCQ
14 Mar 2026
Hydrolysis of sucrose gives :
A.
$\alpha$-D-($-$)-Glucose and $\beta$-D-($-$)-Fructose
B.
$\alpha$-D-(+)-Glucose and $\alpha$-D-($-$)-Fructose
C.
$\alpha$-D-($-$)-Glucose and $\alpha$-D-(+)-Fructose
D.
$\alpha$-D-(+)-Glucose and $\beta$-D-($-$)-Fructose
2021
Q113
JEE Mains
MCQ
14 Mar 2026
Out of following isomeric forms of uracil, which one is present in RNA?
A.
B.
C.
D.
2021
Q114
JEE Mains
MCQ
14 Mar 2026
Given below are two statements : one is labelled as Assertion (A) and other is labelled as Reason (R).
Assertion (A) : Sucrose is a disaccharide and a non-reducing sugar.
Reason (R) : Sucrose involves glycosidic linkage between C1 of $\beta$-glucose and C2 of $\alpha$-fructose.
Choose the most appropriate answer from the options given below :
Assertion (A) : Sucrose is a disaccharide and a non-reducing sugar.
Reason (R) : Sucrose involves glycosidic linkage between C1 of $\beta$-glucose and C2 of $\alpha$-fructose.
Choose the most appropriate answer from the options given below :
A.
Both (A) and (R) are true but (R) is not the true explanation of (A).
B.
(A) is false but (R) is true.
C.
(A) is true but (R) is false.
D.
Both (A) and (R) are true and (R) is the true explanation of (A)
2021
Q115
JEE Mains
MCQ
14 Mar 2026
Compound A gives D-Galactose and D-Glucose on hydrolysis. The compound A is :
A.
Amylose
B.
Sucrose
C.
Maltose
D.
Lactose
2021
Q116
JEE Mains
MCQ
14 Mar 2026
Which one among the following chemical tests is used to distinguish monosaccharide from disaccharide?
A.
Seliwanoff's test
B.
Iodine test
C.
Barfoed test
D.
Tollen's test
2021
Q117
JEE Mains
MCQ
14 Mar 2026
The compound 'A' is a complementary base of _______________ in DNA stands.
A.
Uracil
B.
Guanine
C.
Adenine
D.
Cytosine
2021
Q118
JEE Mains
MCQ
14 Mar 2026
Which one of the following is correct structure for cytosine?
A.
B.
C.
D.
2021
Q119
JEE Mains
MCQ
14 Mar 2026
The water soluble protein is :
A.
Fibrin
B.
Albumin
C.
Myosin
D.
Collagen
2021
Q120
JEE Mains
MCQ
14 Mar 2026
Thiamine and pyridoxine are also known respectively as :
A.
Vitamin B2 and Vitamin E
B.
Vitamin E and Vitamin B2
C.
Vitamin B6 and Vitamin B2
D.
Vitamin B1 and Vitamin B6
2021
Q121
JEE Mains
MCQ
14 Mar 2026
Which one of the following statements is not true about enzymes?
A.
Enzymes are non-specific for a reaction and substrate.
B.
Almost all enzymes are proteins.
C.
Enzymes work as catalysts by lowering the activation energy of a biochemical reaction.
D.
The action of enzymes is temperature and pH specific.
2021
Q122
JEE Mains
MCQ
14 Mar 2026
Identify the incorrect statement from the following
A.
Amylose is a branched chain polymer of glucose
B.
Starch is a polymer of $\alpha$-D glucose
C.
$\beta$-Glycosidic linkage makes cellulose polymer
D.
Glycogen is called as animal starch
2021
Q123
JEE Mains
MCQ
14 Mar 2026
Deficiency of vitamin K causes :
A.
Cheilosis
B.
Decrease in blood clotting time
C.
Increase in blood clotting time
D.
Increase in fragility of RBC's
2021
Q124
JEE Mains
MCQ
14 Mar 2026
A non-reducing sugar "A" hydrolyses to give two reducing mono saccharides. Sugar A is
A.
Fructose
B.
Galactose
C.
Glucose
D.
Sucrose
2021
Q125
JEE Mains
MCQ
14 Mar 2026
${C_{12}}{H_{22}}{O_{11}} + {H_2}O\buildrel {Enzyme\,A} \over
\longrightarrow \mathop {{C_6}{H_{12}}{O_6}}\limits_{Glu\cos e} + \mathop {{C_6}{H_{12}}{O_6}}\limits_{Fructose} $
$\mathop {{C_6}{H_{12}}{O_6}}\limits_{Glu\cos e} \buildrel {Enzyme\,B} \over \longrightarrow 2{C_2}{H_5}OH + 2C{O_2}$
In the above reactions, the enzyme A and enzyme B respectively are :
$\mathop {{C_6}{H_{12}}{O_6}}\limits_{Glu\cos e} \buildrel {Enzyme\,B} \over \longrightarrow 2{C_2}{H_5}OH + 2C{O_2}$
In the above reactions, the enzyme A and enzyme B respectively are :
A.
Zymase and Invertase
B.
Invertase and Amylase
C.
Amylase and Invertase
D.
Invertase and Zymase
2021
Q126
JEE Mains
MCQ
14 Mar 2026
Fructose is an example of :
A.
Heptose
B.
Pyranose
C.
Ketohexose
D.
Aldohexose
2021
Q127
JEE Mains
MCQ
14 Mar 2026
Which of the following is correct structure of tyrosine?
A.
B.
C.
D.
2021
Q128
JEE Mains
MCQ
14 Mar 2026
The secondary structure of protein is stabilised by:
A.
Hydrogen bonding
B.
glycosidic bond
C.
Peptide bond
D.
van der Waals forces
2021
Q129
JEE Mains
MCQ
14 Mar 2026
Which among the following pairs of Vitamins is stored in our body relatively for longer duration?
A.
Thiamine and Vitamin A
B.
Ascorbic acid and Vitamin D
C.
Thiamine and Ascorbic acid
D.
Vitamin A and Vitamin D
2021
Q130
JEE Mains
MCQ
14 Mar 2026
Match List - I with List - II.
Choose the correct answer from the options given below :
| List - I | List - II | ||
|---|---|---|---|
| (a) | Sucrose | (i) | $\beta $-D-Galactose and $\beta $-D-Glucose |
| (b) | Lactose | (ii) | $\alpha $-D-Glucose and $\beta $-D-Fructose |
| (c) | Maltose | (iii) | $\alpha $-D-Glucose and $\alpha $-D-Glucose |
Choose the correct answer from the options given below :
A.
(a) $ \to $ (iii), (b) $ \to $ (ii), (c) $ \to $ (i)
B.
(a) $ \to $ (i), (b) $ \to $ (iii), (c) $ \to $ (ii)
C.
(a) $ \to $ (ii), (b) $ \to $ (i), (c) $ \to $ (iii)
D.
(a) $ \to $ (iii), (b) $ \to $ (i), (c) $ \to $ (ii)
2021
Q131
JEE Mains
MCQ
14 Mar 2026
Which of the following vitamin is helpful in delaying the blood clotting?
A.
Vitamin K
B.
Vitamin C
C.
Vitamin E
D.
Vitamin B
2021
Q132
JEE Mains
MCQ
14 Mar 2026
Which of the following is correct structure of $\alpha$-anomer of maltose?
A.
B.
C.
D.
2021
Q133
JEE Mains
MCQ
14 Mar 2026
Which of the glycosidic linkage between galactose and glucose is present in lactose?
A.
C-1 of galactose and C-6 of glucose
B.
C-1 of glucose and C-6 of galactose
C.
C-1 of galactose and C-4 of glucose
D.
C-1 of glucose and C-4 of galactose
2021
Q134
JEE Mains
MCQ
14 Mar 2026
Match List - I and List - II.
| List I | List II | ||
|---|---|---|---|
| (a) | Valium | (i) | Antifertility drug |
| (b) | Morphine | (ii) | Pernicious anaemia |
| (c) | Norethindrone | (iii) | Analgesic |
| (d) | Vitamin ${B_{12}}$ | (iv) | Tranquilizer |
A.
(a)-(i), (b)-(iii), (c)-(iv), (d)-(ii)
B.
(a)-(iv), (b)-(iii), (c)-(ii), (d)-(i)
C.
(a)-(ii), (b)-(iv), (c)-(iii), (d)-(i)
D.
(a)-(iv), (b)-(iii), (c)-(i), (d)-(ii)
2021
Q135
JEE Mains
MCQ
14 Mar 2026
Out of the following, which type of interaction is reponsible for the stabilisation of $\alpha $-helix structure of proteins ?
A.
Covalent bonding
B.
vander Waals forces
C.
Ionic bonding
D.
Hydrogen bonding
2021
Q136
JEE Mains
Numerical
14 Mar 2026
A peptide synthesized by the reactions of one molecule each of Glycine, Leucine, Aspartic acid and Histidine will have _________ peptide linkages.
Correct Answer: 3
Explanation:
Combination of n amino acids gives a polypeptide
with (n – 1) peptide linkages.
Similarly combination of four amino acids gives a tetrapeptide with three peptide linkages.
Similarly combination of four amino acids gives a tetrapeptide with three peptide linkages.
2021
Q137
JEE Mains
Numerical
14 Mar 2026
The total number of negative charge in the tetrapeptide, Gly-Glu-Asp-Tyr, at pH 12.5 will be ______________. (Integer answer)
Correct Answer: 4
Explanation:
Total negative charge produced = 4.
2020
Q138
JEE Mains
MCQ
14 Mar 2026
Which one of the following statements is not
true?
A.
Lactose contains $\alpha $-glycosidic linkage
between C1 of galactose and C4 of glucose
B.
Lactose is a reducing sugar and it gives
Fehling’s test
C.
On acid hydrolysis, lactose gives one
molecule of D(+)-glucose and one molecule
of D(+)-galactose
D.
Lactose (C11H22O11) is a disaccharide and it
contains 8 hydroxyl groups
Lactose contains $\beta $-glycosidic linkage between C1
of galactose and C4
of glucose.
2020
Q139
JEE Mains
MCQ
14 Mar 2026
Which of the following is not an essential
amino acid :
A.
Valine
B.
Leucine
C.
Lysine
D.
Tyrosine
2020
Q140
JEE Mains
MCQ
14 Mar 2026
Which of the following will react with CHCl3 +
alc. KOH?
A.
Adenine and thymine
B.
Thymine and proline
C.
Adenine and lysine
D.
Adenine and proline
2020
Q141
JEE Mains
MCQ
14 Mar 2026
What are the functional groups present in the
structure of maltose?
A.
One acetal and one ketal
B.
One ketal and one hemiketal
C.
Two acetals
D.
One acetal and one hemiacetal
2020
Q142
JEE Mains
MCQ
14 Mar 2026
The correct observation in the following
reactions is :
A.
Formation of blue colour
B.
Formation of violet colour
C.
Formation of red colour
D.
Gives no colour
2020
Q143
JEE Mains
MCQ
14 Mar 2026
Consider the following rections:
'x', 'y' and 'z' in these reactions are respectively.
'x', 'y' and 'z' in these reactions are respectively.
A.
5, 6, & 5
B.
4, 5 & 5
C.
4, 6 & 5
D.
5, 4 & 5
2020
Q144
JEE Mains
MCQ
14 Mar 2026
Two monomers in maltose are :
A.
$\alpha $-D-glucose and $\alpha $-D-galactose
B.
$\alpha $-D-glucose and $\alpha $-D-Fructose
C.
$\alpha $-D-glucose and $\alpha $-D-glucose
D.
$\alpha $-D-glucose and $\beta $-D-glucose
2020
Q145
JEE Mains
MCQ
14 Mar 2026
Which of the following statement is not true for glucose?
A.
Glucose gives Schiff's test for aldehyde
B.
Glucosse reacts with hydroxylamine to form oxime
C.
The pentaacetate of glucose does not react with hydroxylamine to give oxime
D.
Glucose exists in two crystalline forms $\alpha $ and $\beta $
2020
Q146
JEE Mains
MCQ
14 Mar 2026
Which of the following statements is correct ?
A.
Gluconic acid can from cyclic (acteal/hemiacetal) structure
B.
Gluconic acid is a partial oxidation product of glucose
C.
Gluconic acid is obtained by oxidation of glucose with (HNO3)
D.
Gluconic acid is a dicarboxylic acid.
2020
Q147
JEE Mains
MCQ
14 Mar 2026
Match the following :
(i) Riboflavin (a) Beriberi
(ii) Thiamine (b) Scurvy
(iii) Pyridoxine (c) Cheliosis
(iv) Ascorbic acid (d) Convulsions
(i) Riboflavin (a) Beriberi
(ii) Thiamine (b) Scurvy
(iii) Pyridoxine (c) Cheliosis
(iv) Ascorbic acid (d) Convulsions
A.
(i)-(c), (ii)-(d), (iii)-(a), (iv)-(b)
B.
(i)-(d), (ii)-(b), (iii)-(a), (iv)-(c)
C.
(i)-c, (ii)-(a), (iii)-(d), (iv)-(b)
D.
(i)-(a), (ii)-(d), (iii)-(c), (iv)-(b)
2020
Q148
JEE Mains
Numerical
14 Mar 2026
The number of chiral carbons present in
sucrose is _____.
Correct Answer: 9
Explanation:
Total number of chiral carbon in sucrose = 9
2020
Q149
JEE Mains
Numerical
14 Mar 2026
The number of chiral carbon(s) present in
peptide, Ile-Arg-Pro, is _____.
peptide, Ile-Arg-Pro, is _____.
Correct Answer: 4
Explanation:
The amino acids present in the given tripeptide
I$l$e–Arg–Pro are isoleucine, arginine and proline.
Number of chiral carbons present in the given tripeptide is 4.
Number of chiral carbons present in the given tripeptide is 4.
2020
Q150
JEE Mains
Numerical
14 Mar 2026
The number of chiral centres present in
threonine is ________.
Correct Answer: 2
Explanation:
The structure of threonine is
No. of chiral centres present in it = 2
No. of chiral centres present in it = 2