Please refer to Biomolecules Class 11 Biology Important Questions with answers below. These solved questions for Chapter 9 Biomolecules in NCERT Book for Class 11 Biology have been prepared based on the latest syllabus and examination guidelines issued by CBSE, NCERT, and KVS. Students should learn these solved problems properly as these will help them to get better marks in your class tests and examinations. You will also be able to understand how to write answers properly. Revise these questions and answers regularly. We have provided Notes for Class 11 Biology for all chapters in your textbooks.

Important Questions Class 11 Biology Chapter 9 Biomolecules

Objective Questions

Question. Biomolecules are
(a) organic compounds
(b) inorganic compounds
(c) volatile compounds
(d) both (a) and (b)

Question. All the following amino acids are aromatic, except
(a) tyrosine
(b) phenylalanine
(c) tryptophan
(d) valine

Question. The simplest amino acid is _________.
(a) glycine
(b) proline
(c) leucine
(d) tryptophan

Question. Unsaturated fatty acids have
(a) palmitic acid
(b) oleic acid
(c) high melting point
(d) one or more double bonds

Question. Phospholipids are important cell membrane constituents, because they
(a) contain glycerol.
(b) can form bilayers in water.
(c) combine covalently with protein.
(d) contain polar and non-polar portions.

Question. A fat has
(a) 3 glycerol and one fatty acid molecule.
(b) one glycerol and 3 fatty acid molecules.
(c) 3 glycerol and 3 fatty acid molecules.
(d) one glycerol and one fatty acid molecule.

Question. A nucleotide is formed of
(a) purine, pyrimidine and phosphate
(b) purine, sugar and phosphate
(c) nitrogen base, sugar and phosphate
(d) pyrimidine, sugar and phosphate

Statement Type Questions

Question. Which of the following statement is not true about amino acid?
(a) The amino group and carboxylic group of an amino acid are attached to both amino and carboxylic groups to alpha carbon.
(b) Amino acids have an N-terminus, C-terminus, and R groups.
(c) Amino acid can be classified by the number of peptide bond.
(d) Essential amino acids are not synthesized in the body, therefore have to be provided in the diet.

Question. Select the incorrect statement.
(a) Amino acids are substituents methanes.
(b) Glycerol is a trihydroxy propane.
(c) Lysine is a neutral amino acid.
(d) Lecithin is a phospholipid.

Question. Pick out the correct statement.
(a) Chitin is a homopolymer.
(b) Collagen is the most abundant protein in the whole of the biosphere.
(c) Proteins are linear chains of amino acids linked by peptide bonds.
(d) In a polysaccharide, the individual monosaccharides are linked by a phosphodiester bond.

Question. Which of the following statement is incorrect regarding secondary metabolites ?
(a) Plant tissues produce only secondary metabolities.
(b) Secondary metabolities have restricted distribution in the plant kingdoms.
(c) Abrin and ricin are secondary metabolities used as a drugs.
(d) Some secondary metabolites have ecological importance.

Matching Type Questions

Question. Match the biomoecules given in column I with their examples given in column II and choose the correct answer.

Column I (Biomolecules)	Column II (Examples)
A. Carbohydrates	I. Trypsin
B. Protein	II. Cholesterol
C. Nucleic acid	III. Insulin
D. Lipid	IV. Adenylic acid

(a) A – III; B – I; C – IV, D – II
(b) A – II; B – III; C – IV, D – I
(c) A – III; B – IV; C – I, D – II
(d) A – IV; B – I; C – II, D – III

Question. Match the column-I (component) with column-II (% of the total cellular mass) and identify the correct option.

Column-I (Component)	Column-II (% of the total cellular mass)
A. Water	I. 3
B. Proteins	II. 70-90
C. Carbohydrates	III. 2
D. Lipids	IV. 5-7
E. Nucleic acids	V. 10-15

(a) A – V; B – II; C – III; D – IV; E – I
(b) A – II; B – V; C – I; D – III; E – IV
(c) A – III; B – I; C – IV; D – V; E – II
(d) A – V; B – IV; C – III; D – II; E – I

Question. Match column I with column II and choose the correct option.

Column-I	Column-II
A. Cotton fibre	I. Chitin
B. Exoskeleton of cockroach	II. Glycogen
C. Liver	III. Starch
D. Peeled potato	IV. Cellulose

(a) A – I; B – IV; C – III; D – II
(b) A – IV; B – I; C – II; D – III
(c) A – IV; B – I; C – III; D – II
(d) A – I; B – IV; C – II; D – III

Question. Which one of the following pairs of nitrogenous bases of nucleic acids, is wrongly matched with the category mentioned against it ?
(a) Adenine, thymine – Purines
(b) Thymine, uracil – Pyrimidines
(c) Uracil, cytosine – Pyrimidines
(d) Guanine, adenine – Purines

Critical Thinking Type Questions

Question. In the composition of cellular mass, arrange the components- proteins(P), carbohydrates(C), lipids(L) and nucleic acids(N) in decreasing order of mass percentage.
(a) C > N > P > L
(b) P > N > C > L
(c) P > C > L > N
(d) P > N > L > C

Question. Relation between amino acid and protein is similar to the one found between
(a) glucose and fructose
(b) thymine and uracil
(c) nucleosides and nucleic acid
(d) nucleotides and nucleic acid

Question. Antiparallel strands of a DNA molecule means that
(a) the phosphate groups of two DNA strands, at their ends share the same position.
(b) the phosphate groups at the start of two DNA strands are in opposite position (pole).
(c) one strand turns clockwise.
(d) one strand turns anti-clockwise.

Question. “All enzymes are proteins.” This statement is now modified because an apparent exception to this biological truth is
(a) arylsulfatase
(b) dehydrogenase
(c) ribozyme
(d) nitroreductase

Question. Which one of the following biomolecules is correctly characterized?
(a) Lecithin – A phosphorylated glyceride found in cell membrane.
(b) Palmitic acid – An unsaturated fatty acid with 18 carbon atoms.
(c) Adenylic acid – Adenosine with a glucose phosphate molecule.
(d) Alanine amino acid – Contains an amino group and an acidic group anywhere in the molecule.

Question. Which of the following set is correctly match to the category mentioned against them ?
(a) Lysine, glycine, thiamine – amino acids.
(b) Arachidonic acid, acetic acid, palmitic acid – Fatty acids
(c) Thymidine, uridine, cytidilic acid – Nucleosides
(d) Cellulose, inulin, glycogen – Polysaccharides

Question. Select the type of enzyme involved in the following reaction.
S-G + S’→S+ S’-G
(a) Dehydrogenase
(b) Transferase
(c) Hydrolase
(d) Lyase

Diagram Type Questions

Question. Identify the following molecule.

(a) Phospholipid
(b) Lecithin
(c) Cholesterol
(d) Oleic acid

Question. The given structural formulas represent amino acids (labelled by as X, Y and Z)

Identify the correct name of X, Y and Z.
(a) Alanine, serine and glycine respectively.
(b) Tyrosine, cysteine and glutamic acid respectively.
(c) Glycine, alanine and serine acid respectively.
(d) Cysteine, glutamic acid and tyrosine respectively.

Question. What is denoted by X and Y in the given graph ?

X	Y
(a) Activation energy without enzyme	Activation energy with enzyme
(b) Activation energy with enzyme	Activation energy without enzyme
(c) Substrate concentration  with enzyme	Substrate concentration without enzyme
(d) Substrate concentration without enzyme	Substrate concentration with enzyme

Question. The given diagrammatic representation shows one of the categories of small molecular weight organic compounds in the living tissues. Identify the category shown and one blank component marked as “X” in it.

Category	Component (X)
(a) Cholesterol	Guanine
(b) Amino acid	NH2
(c) Nucleotide	Adenine
(d) Nucleoside	Uracil

Question. Which of the following shows zwitter ionic form?