MCQs For NCERT Class 11 Biology Chapter 9 Biomolecules

Please refer to the MCQ Questions for Class 11 Biology Chapter 9 Biomolecules with Answers. The following Biomolecules Class 11 Biology MCQ Questions have been designed based on the latest syllabus and examination pattern for Class 11. Our experts have designed MCQ Questions for Class 11 Biology with Answers for all chapters in your NCERT Class 11 Biology book.

Biomolecules Class 11 MCQ Questions with Answers

See below Biomolecules Class 11 Biology MCQ Questions, solve the questions and compare your answers with the solutions provided below.

Question. Three of the following statements about enzymes are correct and one is wrong. Which one is wrong?    
(a) Enzymes require optimum pH for maximal activity.
(b) Enzymes are denatured at high temperature but in certain exceptional organisms they are effective even at temperatures 80° – 90°C.
(c) Enzymes are highly specific.
(d) Most enzymes are proteins but some are lipids. 

Question. Which factor is responsible for inhibition of enzymatic process during feedback?   
(a) Substrate
(b) Enzymes
(c) End product
(d) Temperature

Question. Which of the following statements is correct with reference to enzymes? 
(a) Holoenzyme = Apoenzyme + Coenzyme
(b) Coenzyme = Apoenzyme + Holoenzyme
(c) Holoenzyme = Coenzyme + Co-factor
(d) Apoenzyme = Holoenzyme + Coenzyme

Question. Which of the following have carbohydrate as prosthetic group?   
(a) Glycoprotein
(b) Chromoprotein
(c) Lipoprotein
(d) Nucleoprotein

Question. Cellulose, the most important constituent of plant cell wall is made up of   
(a) branched chain of glucose molecules linked by β-1, 4 glycosidic bond in straight chain and α-1,6 glycosidic bond at the site of branching
(b) unbranched chain of glucose molecules linked by β-1, 4 glycosidic bond
(c) branched chain of glucose molecules linked by α-1, 6 glycosidic bond at the site of branching
(d) unbranched chain of glucose molecules linked by α-1, 4 glycosidic bond.

Question. Lactose is composed of   
(a) glucose + galactose
(b) fructose + galactose
(c) glucose + fructose
(d) glucose + glucose.

Question. In which of the following groups are all polysaccharides?   
(a) Sucrose, glucose and fructose
(b) Maltose, lactose and fructose
(c) Glycogen, sucrose and maltose
(d) Glycogen, cellulose and starch

Question. Glycogen is a polymer of   
(a) galactose
(b) glucose
(c) fructose
(d) sucrose.

Question. Which of the following biomolecules does have a phosphodiester bond?   
(a) Amino acids in a polypeptide
(b) Nucleic acids in a nucleotide
(c) Fatty acids in a diglyceride
(d) Monosaccharides in a polysaccharide

Question. Which is wrong about nucleic acids?   
(a) DNA is single stranded in some viruses.
(b) RNA is double stranded occasionally.
(c) Length of one helix is 45 Å in B-DNA.
(d) One turn of Z-DNA has 12 bases.

Question. Which of the following are not polymeric?   
(a) Proteins
(b) Polysaccharides
(c) Lipids
(d) Nucleic acids

Question. Nucleotides are building blocks of nucleic acids.   
Each nucleotide is a composite molecule formed by
(a) base-sugar-phosphate
(b) base-sugar-OH
(c) (base-sugar-phosphate)n
(d) sugar-phosphate.

Question. Which of the following nucleotide sequences contains 4 pyrimidine bases?   
(a) GATCAATGC
(b) GCUAGACAA
(c) UAGCGGUAA
(d) Both (b) and (c)

Question. Transition state structure of the substrate formed during an enzymatic reaction is   
(a) transient and unstable
(b) permanent and stable
(c) transient but stable
(d) permanent but unstable.

Question. The essential chemical components of many coenzymes are   
(a) carbohydrates
(b) vitamins
(c) proteins
(d) nucleic acids.

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.

Question. In which one of the following enzymes, is copper necessarily associated as an activator?   
(a) Carbonic anhydrase
(b) Tryptophanase
(c) Lactic dehydrogenase
(d) Tyrosinase

Question. DNA is composed of repeating units of   
(a) ribonucleosides
(b) deoxyribonucleosides
(c) ribonucleotides
(d) deoxyribonucleotides.

Question. Carbohydrates, the most abundant biomolecule on earth, are produced by   
(a) some bacteria, algae and green plant cells
(b) fungi, algae and green plant cells
(c) all bacteria, fungi and algae
(d) viruses, fungi and bacteria.

Question. Which of the following is a reducing sugar?   
(a) Galactose
(b) Gluconic acid
(c) β-methyl galactoside
(d) Sucrose 

Question. A competitive inhibitor of succinic dehydrogenase is   
(a) α-ketoglutarate
(b) malate
(c) malonate
(d) oxaloacetate.

Question. Adenine is   
(a) purine
(b) pyrimidine
(c) nucleoside
(d) nucleotide.

Question. Select the option which is not correct with respect to enzyme action.   
(a) Substrate binds with enzyme at its active site.
(b) Addition of lot of succinate does not reverse the inhibition of succinic dehydrogenase by malonate.
(c) A non-competitive inhibitor binds the enzyme at a site distinct from that which binds the substrate.
(d) Malonate is a competitive inhibitor of succinic dehydrogenase.

Question. Which one of the following statements regarding enzyme inhibition is correct?   
(a) Competitive inhibition is seen when a substrate competes with an enzyme for binding to an inhibitor protein.
(b) Competitive inhibition is seen when the substrate and the inhibitor compete for the active site on the enzyme.
(c) Non-competitive inhibition of an enzyme can be overcome by adding large amount of substrate.
(d) Non-competitive inhibitors often bind to the enzyme irreversibly.

Question. Which of the following is the least likely to be involved in stabilising the three-dimensional folding of most proteins?   
(a) Hydrogen bonds
(b) Electrostatic interaction
(c) Hydrophobic interaction
(d) Ester bonds

Question. Identify the substances having glycosidic bond and peptide bond, respectively in their structure. 
(a) Chitin, cholesterol
(b) Glycerol, trypsin
(c) Cellulose, lecithin
(d) Inulin, insulin

Question. Which is not consistent with double helical structure of DNA? 
(a) A = T, C = G
(b) Density of DNA decreases on heating.
(c) A + T/C + G is not constant.
(d) Both (a) and (b)

Question. Match the following.   
(A) Inhibitor of (i) Ricin catalytic activity
(B) Possess peptide (ii) Malonate bonds
(C) Cell wall material (iii) Chitin in fungi
(D) Secondary (iv) Collagen metabolite
Choose the correct option from the following:
(A) (B) (C) (D)
(a) (ii) (iv) (iii) (i)
(b) (iii) (i) (iv) (ii)
(c) (iii) (iv) (i) (ii)
(d) (ii) (iii) (i) (iv)

Question. Enzymes, vitamins and hormones can be classified into a single category of biological chemicals, because all of these   
(a) help in regulating metabolism
(b) are exclusively synthesized in the body of a living organism as at present
(c) are conjugated proteins
(d) enhance oxidative metabolism.

Question. Consider the following statements.   
(A) Coenzyme or metal ion that is tightly bound to enzyme protein is called prosthetic group.
(B) A complete catalytic active enzyme with its bound prosthetic group is called apoenzyme.
Select the correct option.
(a) (A) is false but (B) is true.
(b) Both (A) and (B) are true.
(c) (A) is true but (B) is false.
(d) Both (A) and (B) are false.

Question. Cellulose is the major component of cell walls of   
(a) Pseudomonas
(b) Saccharomyces
(c) Pythium
(d) Xanthomonas.

Question. In double helix of DNA, the two DNA strands are   
(a) coiled around a common axis
(b) coiled around each other
(c) coiled differently
(d) coiled over protein sheath.

Question. ATP is   
(a) nucleotide
(b) nucleoside
(c) nucleic acid
(d) vitamin.

Question. Prosthetic groups differ from co-enzymes in that 
(a) they require metal ions for their activity
(b) they (prosthetic groups) are tightly bound to apoenzymes
(c) their association with apoenzymes is transient
(d) they can serve as co-factors in a number of enzyme-catalyzed reactions.

Question. In RNA, thymine is replaced by   
(a) adenine
(b) guanine
(c) cytosine
(d) uracil.