Chapter Exam

Chapter-10 Biomolecules — Online MCQ Test

Q: Carbohydrates are primarily composed of which three elements?

Answer: B. Carbon, Hydrogen, and Oxygen — Carbohydrates follow the general formula Cn(H2O)m and contain only carbon, hydrogen, and oxygen.

Q: Which of the following is a monosaccharide?

Answer: C. Glucose — Glucose is a monosaccharide with 6 carbons (C6H12O6), while sucrose and maltose are disaccharides, and starch is a polysaccharide.

Q: Starch and cellulose are both polysaccharides, but they differ in their:

Answer: C. Glycosidic linkages and biological function — Both are glucose polymers, but starch has α-1,4-glycosidic bonds and is digestible, while cellulose has β-1,4-glycosidic bonds and is not digestible by humans.

Q: A student analyzes a biomolecule and finds: (1) It contains nitrogen but no phosphorus, (2) It yields amino acids upon hydrolysis, (3) It forms a purple complex with biuret reagent. This biomolecule is definitely:

Answer: C. A protein — Amino acids upon hydrolysis, nitrogen content, and positive biuret test (peptide bonds) are all characteristic of proteins.

CHEMISTRY · Grade 12 · CBSE(NCERT)

Practice Chapter-10 Biomolecules with a free chapter-wise online MCQ test for CBSE(NCERT) Grade 12 CHEMISTRY. This chapter covers: carbohydrates - proteins - vitamins - nucleic acids - DNA - RNA. AI-generated questions from basic to board-exam level, with instant results and explanations.

Questions

20m

Time Limit

Attempts Left

10 random questions from this chapter (mixed difficulty)
Questions you've seen before won't repeat until the pool resets
You have 20 minutes — exam auto-submits when time is up
Maximum 3 attempts per chapter
Results and explanations shown immediately after submission

New here? Register free — includes 3 free chapter exams.

Chapter-10 Biomolecules — Important Questions & Answers (FAQ)

Frequently asked questions from CBSE(NCERT) Grade 12 CHEMISTRY — Chapter-10 Biomolecules, with answers and explanations. These are sample questions; the exam has its own separate question set.

Carbohydrates are primarily composed of which three elements?

A. Carbon, Hydrogen, and Nitrogen
B. Carbon, Hydrogen, and Oxygen ✓
C. Carbon, Oxygen, and Sulfur
D. Hydrogen, Oxygen, and Nitrogen

Answer: B. Carbon, Hydrogen, and Oxygen
Carbohydrates follow the general formula Cn(H2O)m and contain only carbon, hydrogen, and oxygen.

Which of the following is a monosaccharide?

A. Sucrose
B. Maltose
C. Glucose ✓
D. Starch

Answer: C. Glucose
Glucose is a monosaccharide with 6 carbons (C6H12O6), while sucrose and maltose are disaccharides, and starch is a polysaccharide.

Starch and cellulose are both polysaccharides, but they differ in their:

A. Molecular formula
B. Monosaccharide units
C. Glycosidic linkages and biological function ✓
D. Number of carbons

Answer: C. Glycosidic linkages and biological function
Both are glucose polymers, but starch has α-1,4-glycosidic bonds and is digestible, while cellulose has β-1,4-glycosidic bonds and is not digestible by humans.

Compare starch, cellulose, and glycogen. Which statement is CORRECT?

A. All three are glucose polymers with identical glycosidic linkages
B. Starch and cellulose contain α-bonds; glycogen contains β-bonds
C. Glycogen and starch are storage polysaccharides; cellulose provides structural support ✓
D. Cellulose is easily digested in human stomachs because it's a glucose polymer

Answer: C. Glycogen and starch are storage polysaccharides; cellulose provides structural support
Starch (in plants) and glycogen (in animals) are storage polysaccharides with α-1,4-glycosidic bonds; cellulose has β-1,4-bonds and serves a structural role.

A student analyzes a biomolecule and finds: (1) It contains nitrogen but no phosphorus, (2) It yields amino acids upon hydrolysis, (3) It forms a purple complex with biuret reagent. This biomolecule is definitely: