JEE Chemistry Biomolecules MCQs Set 14

Practice MCQs for JEE Chemistry Biomolecules

Review structured MCQ sets for JEE Chemistry Biomolecules. Built according to official JEE guidelines, these downloadable questions support daily revision and core concept reinforcement.

Access Biomolecules Questions and Solutions

Access the complete set of multiple-choice questions for Biomolecules below. This focused format allows students to isolate specific topics for thorough review and uninterrupted practice alongside official JEE textbooks.

Multiple Choice Questions

Question 1: The specific rotation of the equilibrium mixture of alpha-D-glucose and beta-D-glucose is
(a) +19 degrees
(b) +112 degrees
(c) +52 degrees
(d) +100 degrees
Show Answer & Explanation

Answer: (c) +52 degrees

Explanation:
1. The alpha form (+112) and beta form (+19) reach an equilibrium rotation of +52.5 degrees.

Teacher's Note:
1. Always link acid strength to the stability of the carboxylate ion.
2. Electron-withdrawing groups increase acidity and electron-donating groups decrease it.

Question 2: The charring of sugar when treated with conc. H2SO4 is due to
(a) oxidation
(b) reduction
(c) dehydration
(d) hydrolysis
Show Answer & Explanation

Answer: (c) dehydration

Explanation:
1. The acid removes water and leaves carbon.

Teacher's Note:
1. Note the name reaction and write its equation once in your notebook.
2. Such one-step recall questions are common in the JEE and NEET style papers.

Question 3: Which among the following is the simplest sugar?
(a) glucose
(b) cellulose
(c) starch
(d) glycogen
Show Answer & Explanation

Answer: (a) glucose

Explanation:
1. The others are polysaccharides.

Teacher's Note:
1. Count carbons before and after the reaction to avoid mistakes in chain-length changes.
2. Check whether the reagent is a reducing, oxidising or dehydrating agent before choosing the product.

Question 4: Glucose and mannose are
(a) epimers
(b) anomers
(c) ketohexoses
(d) disaccharides
Show Answer & Explanation

Answer: (a) epimers

Explanation:
1. They differ in configuration only at C2.

Teacher's Note:
1. Eliminate options by checking functional groups on both sides of the reaction.
2. Only one option will have the correct functional group and carbon skeleton.

Question 5: Pick out the one which does not belong to the family of enzymes.
(a) pepsin
(b) cellulose
(c) ptyalin
(d) lipase
Show Answer & Explanation

Answer: (b) cellulose

Explanation:
1. Cellulose is a polysaccharide and the others are enzymes.

Teacher's Note:
1. Revise the physical properties such as hydrogen bonding and boiling points together with the chemistry.
2. Compare similar compounds in pairs when you are asked to rank them.

Question 6: Which of the following is the sweetest sugar?
(a) glucose
(b) fructose
(c) lactose
(d) sucrose
Show Answer & Explanation

Answer: (b) fructose

Explanation:
1. Fructose is the sweetest natural sugar.

Teacher's Note:
1. Learn the reactivity order of acid derivatives: acyl chloride, anhydride, ester, amide.
2. Most questions of this type are solved by recalling the standard reagent and product pair.

Question 7: In fructose, the number of possible optical isomers is
(a) 12
(b) 8
(c) 16
(d) 4
Show Answer & Explanation

Answer: (b) 8

Explanation:
1. D-Fructose has three chiral carbons, so 23 = 8 isomers.

Teacher's Note:
1. Always link acid strength to the stability of the carboxylate ion.
2. Electron-withdrawing groups increase acidity and electron-donating groups decrease it.

Question 8: If an aqueous solution of glucose is allowed to freeze, then which crystal will separate out first?
(a) glucose
(b) water
(c) both of these
(d) none of these
Show Answer & Explanation

Answer: (b) water

Explanation:
1. The freezing point is lowered, and ice (pure water) crystallises first.

Teacher's Note:
1. Note the name reaction and write its equation once in your notebook.
2. Such one-step recall questions are common in the JEE and NEET style papers.

Question 9: Which statement is false?
(a) glucose is a disaccharide
(b) starch is a polysaccharide
(c) glucose and fructose are not anomers
(d) invert sugar consists of glucose and fructose
Show Answer & Explanation

Answer: (a) glucose is a disaccharide

Explanation:
1. Glucose is a monosaccharide.

Teacher's Note:
1. Count carbons before and after the reaction to avoid mistakes in chain-length changes.
2. Check whether the reagent is a reducing, oxidising or dehydrating agent before choosing the product.

Question 10: Insulin is
(a) an amino acid
(b) a protein
(c) a carbohydrate
(d) a lipid
Show Answer & Explanation

Answer: (b) a protein

Explanation:
1. Insulin is a polypeptide hormone of 51 amino acid residues.

Teacher's Note:
1. Eliminate options by checking functional groups on both sides of the reaction.
2. Only one option will have the correct functional group and carbon skeleton.

Question 11: Peptides are
(a) esters
(b) salts
(c) amides
(d) ketones
Show Answer & Explanation

Answer: (c) amides

Explanation:
1. Peptides contain -CO-NH- amide links.

Teacher's Note:
1. Revise the physical properties such as hydrogen bonding and boiling points together with the chemistry.
2. Compare similar compounds in pairs when you are asked to rank them.

Question 12: The proteins which are insoluble in water are
(a) fibrous proteins
(b) globular proteins
(c) both (a) and (b)
(d) none of these
Show Answer & Explanation

Answer: (a) fibrous proteins

Explanation:
1. Fibrous proteins such as keratin and collagen are insoluble in water.
2. Globular proteins are soluble.

Teacher's Note:
1. Learn the reactivity order of acid derivatives: acyl chloride, anhydride, ester, amide.
2. Most questions of this type are solved by recalling the standard reagent and product pair.

Question 13: Irreversible precipitation of proteins is called
(a) denaturation
(b) hydrolysis
(c) rearrangement
(d) electrophoresis
Show Answer & Explanation

Answer: (a) denaturation

Explanation:
1. Heat or acid destroys the secondary and tertiary structure permanently, as in a boiled egg.

Teacher's Note:
1. Always link acid strength to the stability of the carboxylate ion.
2. Electron-withdrawing groups increase acidity and electron-donating groups decrease it.

Question 14: The proteins with a prosthetic group are called
(a) pseudo proteins
(b) complex proteins
(c) conjugated proteins
(d) polypeptides
Show Answer & Explanation

Answer: (c) conjugated proteins

Explanation:
1. Conjugated proteins have a non-protein prosthetic group.

Teacher's Note:
1. Note the name reaction and write its equation once in your notebook.
2. Such one-step recall questions are common in the JEE and NEET style papers.

Question 15: The prosthetic group of haemoglobin is
(a) porphin
(b) haem
(c) globin
(d) globulin
Show Answer & Explanation

Answer: (b) haem

Explanation:
1. Haem, an iron(II) porphyrin, is bound to the globin protein.

Teacher's Note:
1. Count carbons before and after the reaction to avoid mistakes in chain-length changes.
2. Check whether the reagent is a reducing, oxidising or dehydrating agent before choosing the product.

Question 16: When collagen is boiled with water, it forms
(a) a precipitate
(b) a solution
(c) gelatin
(d) complex collagen
Show Answer & Explanation

Answer: (c) gelatin

Explanation:
1. Gelatin is partly hydrolysed collagen.

Teacher's Note:
1. Eliminate options by checking functional groups on both sides of the reaction.
2. Only one option will have the correct functional group and carbon skeleton.

Question 17: Which of the following is not an essential amino acid?
(a) valine
(b) lysine
(c) histidine
(d) glycine
Show Answer & Explanation

Answer: (d) glycine

Explanation:
1. The body can synthesise glycine.

Teacher's Note:
1. Revise the physical properties such as hydrogen bonding and boiling points together with the chemistry.
2. Compare similar compounds in pairs when you are asked to rank them.

Question 18: Amino acids are
(a) liquids
(b) volatile solids
(c) non-volatile crystalline compounds
(d) mixtures of amines and acids
Show Answer & Explanation

Answer: (c) non-volatile crystalline compounds

Explanation:
1. Dipolar ions give high melting points.

Teacher's Note:
1. Learn the reactivity order of acid derivatives: acyl chloride, anhydride, ester, amide.
2. Most questions of this type are solved by recalling the standard reagent and product pair.

Question 19: The isoelectric point is the
(a) specific temperature
(b) suitable concentration of the amino acid
(c) hydrogen ion concentration that does not allow migration of the amino acid under an electric field
(d) melting point of an amino acid under the influence of an electric field
Show Answer & Explanation

Answer: (c) hydrogen ion concentration that does not allow migration of the amino acid under an electric field

Explanation:
1. At the isoelectric pH the amino acid is a zwitterion with zero net charge.

Teacher's Note:
1. Always link acid strength to the stability of the carboxylate ion.
2. Electron-withdrawing groups increase acidity and electron-donating groups decrease it.

Question 20: Proteins are hydrolysed by enzymes into
(a) dicarboxylic acids
(b) hydroxy acids
(c) amino acids
(d) aromatic acids
Show Answer & Explanation

Answer: (c) amino acids

Explanation:
1. Proteolytic enzymes cleave peptide bonds.

Teacher's Note:
1. Note the name reaction and write its equation once in your notebook.
2. Such one-step recall questions are common in the JEE and NEET style papers.

Question 21: Proteins when heated with conc. HNO3 give a yellow colour. This is
(a) an oxidising test
(b) the xanthoproteic test
(c) Hoppe's test
(d) an acid-base test
Show Answer & Explanation

Answer: (b) the xanthoproteic test

Explanation:
1. Nitration of aromatic rings in tyrosine and phenylalanine gives a yellow colour.

Teacher's Note:
1. Count carbons before and after the reaction to avoid mistakes in chain-length changes.
2. Check whether the reagent is a reducing, oxidising or dehydrating agent before choosing the product.

Question 22: Enzymes are
(a) proteins
(b) minerals
(c) oils
(d) fatty acids
Show Answer & Explanation

Answer: (a) proteins

Explanation:
1. Enzymes are globular proteins.

Teacher's Note:
1. Eliminate options by checking functional groups on both sides of the reaction.
2. Only one option will have the correct functional group and carbon skeleton.

Question 23: Proteins are built up of
(a) dicarboxylic acids
(b) amino acids
(c) alcohols
(d) hydroxy acids
Show Answer & Explanation

Answer: (b) amino acids

Explanation:
1. They are polymers of alpha-amino acids.

Teacher's Note:
1. Revise the physical properties such as hydrogen bonding and boiling points together with the chemistry.
2. Compare similar compounds in pairs when you are asked to rank them.

Question 24: The main structural feature of proteins is
(a) the ester linkage
(b) the ether linkage
(c) the peptide linkage
(d) all of these
Show Answer & Explanation

Answer: (c) the peptide linkage

Explanation:
1. Amino acids are joined by -CO-NH- bonds.

Teacher's Note:
1. Learn the reactivity order of acid derivatives: acyl chloride, anhydride, ester, amide.
2. Most questions of this type are solved by recalling the standard reagent and product pair.

Question 25: Pepsin enzyme hydrolyses
(a) proteins to amino acids
(b) fats to fatty acids
(c) glucose to ethyl alcohol
(d) polysaccharides to monosaccharides
Show Answer & Explanation

Answer: (a) proteins to amino acids

Explanation:
1. Pepsin in the stomach breaks proteins into smaller peptides and amino acids.

Teacher's Note:
1. Always link acid strength to the stability of the carboxylate ion.
2. Electron-withdrawing groups increase acidity and electron-donating groups decrease it.

Question 26: Which one of the following proteins transports oxygen in the blood stream?
(a) myoglobin
(b) insulin
(c) albumin
(d) haemoglobin
Show Answer & Explanation

Answer: (d) haemoglobin

Explanation:
1. Haemoglobin carries oxygen in red blood cells.
2. Myoglobin stores it in muscle.

Teacher's Note:
1. Note the name reaction and write its equation once in your notebook.
2. Such one-step recall questions are common in the JEE and NEET style papers.

Question 27: Enzymes are
(a) living organisms
(b) dead organisms
(c) complex nitrogenous substances produced in living cells
(d) none of these
Show Answer & Explanation

Answer: (c) complex nitrogenous substances produced in living cells

Explanation:
1. Enzymes are protein catalysts made by cells.

Teacher's Note:
1. Count carbons before and after the reaction to avoid mistakes in chain-length changes.
2. Check whether the reagent is a reducing, oxidising or dehydrating agent before choosing the product.

Free study material for Chemistry

Practice MCQs for JEE Chemistry Biomolecules

JEE Chemistry Biomolecules Objective Test Questions

Test your conceptual understanding of Biomolecules with these targeted multiple-choice questions. Designed in alignment with the latest JEE curriculum for JEE Chemistry, these problem sets build accuracy and prepare students for objective exams.

NCERT-Aligned Objective Questions and Solutions

Cross-reference your completed choices with comprehensive NCERT solutions for JEE Chemistry to ensure absolute clarity across all sub-topics in this chapter.

Next Steps in Your Exam Preparation

Wrap up your chapter revision by testing your knowledge against standard question formats. Everything on our platform is provided free of charge.

FAQs

Where can I access latest JEE Chemistry Biomolecules MCQs Set 14?

You can get most exhaustive JEE Chemistry Biomolecules MCQs Set 14 for free on StudiesToday.com. These MCQs for JEE Chemistry are updated for the 2026-27 academic session as per JEE examination standards.

Are Assertion-Reasoning and Case-Study MCQs included in the Chemistry JEE material?

Yes, our JEE Chemistry Biomolecules MCQs Set 14 include the latest type of questions, such as Assertion-Reasoning and Case-based MCQs. 50% of the JEE paper is now competency-based.

How do practicing Chemistry MCQs help in scoring full marks in JEE exams?

By solving our JEE Chemistry Biomolecules MCQs Set 14, JEE students can improve their accuracy and speed which is important as objective questions provide a chance to secure 100% marks in the Chemistry.

Do you provide answers and explanations for JEE Chemistry Biomolecules MCQs Set 14?

Yes, Chemistry MCQs for JEE have answer key and brief explanations to help students understand logic behind the correct option as its important for 2026 competency-focused JEE exams.

Can I practice these Chemistry JEE MCQs online?

Yes, you can also access online interactive tests for JEE Chemistry Biomolecules MCQs Set 14 on StudiesToday.com as they provide instant answers and score to help you track your progress in Chemistry.