CBSE Class 12 Chemistry Biomolecules MCQs Set 05

Question: The sugar moiety present RNA molecule is 
(a) β-D-2-deoxyribose
(b) β-D-galactose
(c) β-D-fructofuranose
(d) β-D-ribose
(e) β-D-glucopyranose
Answer: d

Question: Which of the following element is present in haemoglobin?
(a) Na
(b) Ca 
(c) Fe
(d) Au
Answer: c  

Question: The secondary structure of a protein refers to 
(a) α-helical backbone
(b) hydrophobic interactions
(c) sequence of a -amino acids
(d) fixed configmatjon of the polypeptide backbone
Answer: a

Question: Which one of the following is not a protein? 
(a) Wool
(b) Nail
(c) Hair
(d) DNA
Answer: d  

Question: Which amino acid has irnidazole ring? 
(a) Alanine
(b) Leucine
(c) Tyrosine
(d) Histidine
Answer: d

Question: Which destroy antigens?
(a) Insulin
(b) Antibodies
(c) Chromoprotein
(d) Phosphoprotein
Answer: b  

Question: Which of the following is a simplest amino acids?
(a) Glycine
(b) Alanine
(c) Leucine
(d) Valine
 Answer: a

Question: Which one of the following statements about amino acids is not trne?
(a) They are constituents of all proteins
(b) They are all high melting solids
(c) Most naturally occurring amino acids have D-configuration
(d) They are characterised by isoelectric point
Answer: c

Question: Which one of the following is a conjugated protein?
(a) Phosphoprotein
(b) Glycoprotein
(c) Chromoprotein
(d) All of these   
Answer: d

Question: Give the pOH range for the isoelectric point of the amphoteric ion of an amino acid 
(a) 5.5 to 6.3
(b) 2.5 to 5.0
(c) 7.7 to 8.5
(d) 9.0 to 10.7
Answer: c

Question: A nanopeptide contains .... .. peptide linkages. 
(a) 10
(b) 8
(c) 9
(d) 18 
Answer: b

Question: In aqueous solution, amino acids mostly exist as 
(a) NH₂ — CHR — COOH
(b) NH₂ — CHR — COO^-
(c) NH⁺₃ — CHR — COOH
(d) NH⁺₃ — CHR — COO^-
Answer: d

Question: In DNA, the consecutive deoxynucleotides are connected via 
(a) phosphocliester linkage
(b) phosphomonoester linkage
(c) phosphotriester linkage
(d) amide linkage
Answer: a

Question: Proteins are 
(a) polypeptides with low molecular weights
(b) polypeptides with high molecular weights
(c) polymers of amides
(d) polymers of secondary amines
Answer: b

Question: Progesterone is secreted by ... . . . . 
(a) thyroid
(b) ovaries
(c) adrenal
(d) testes
Answer: b

Question: Metabolic function in hwnan bodies is carried out by
(a) lipids
(b) peptides 
(c) nucleic acid
(d) enzymes
Answer: d 

Question: The product formed in the reaction of glycine with benzoyl chloride+ aq. NaOH is 
(a) PhCOCH₂NH₂
(b) PhCH₂NH₂
(c) PhCONHCH₃
(d) PhCONHCH₂CO₂H
Answer: d

Question: An achiral amino acid
(a) alanine
(b) valine
(c) leucine
(d) glycine
Answer: d

Question: An electric current is passed through an aqueous solution of a mixture of alanine (isoelectric point 6.0) glutamic acid (3.2) and arginine (10.7) buffered at pH 6. What is the fate of the three acids? 
(a) Glutamic acid migrates to anode at pH 6. Arginine present as a cation and migrates to the cathode Alanine in a dipolar ion remains uniformly distributed in solution
(b) Glutamic acid migrates to cathode and others remain uniformly distributed in solution
(c) All three remain uniformly distributed in solution 
(d) All three move to cathode
Answer: a

Question: Which of the following is present in animals like cow, buffaloes etc. to digest compound like paper, cloth etc?
(a) Urease
(b) Cellulase
(c) Silicones
(d) Sucrose
Answer: b

Question: α-helix is found in
(a) DNA
(b) RNA
(c) lipid
(d) carbohydrates
(e) protein
Answer: e

Question: Which of the following is true?
(a) Nucleoside + phosphoester bond= nucleotide
(b) DNA's are nucleotide and RNA's are nucleoside
(c) Nucleotide + phosphoester bond= nucleoside
(d) None of the above
Answer: a

Question: Which of the following exists as Zwitter ion ?
(a) p-aminophenol 
(b) Salicylic acid
(c) Sulphanilic acid
(d) Ethanolamine
(e) p-amino acetophenone
Answer: c 

Question: RNA contains
(a) ribose sugar and thymine
(b) ribose sugar and uracil
(c) deoxyribose sugar and uracil
(d) deoxyribose sugar and thymine 
Answer: b

Question: The enzyme pepsin hydrolyses 
(a) proteins to amino acids
(b) fats to fatty acids
(c) glucose to ethyl alcohol
(d) poloysaccharides to monosaccharides
Answer: a

Question: Which of the following biomolecules acts as specific catalysts in biological reaction ? 
(a) Carbohydrates
(b) Lipids
(c) Vitamins
(d) Enzymes
Answer: d

Question: The enzyme that is used to dissolve blood clot is 
(a) trypsin
(b) renin
(c) streptokinase
(d) tyrosinase
Answer: c

Question: Protein gives blue colour with 
(a) benedict reagent
(b) iodine solution
(c) ninhydrin
(d) biurete 
Answer: c 

Question: Peptides are formed from
(a) aliphatic amines
(c) a -amino acids
(b) carbohydrates
(d) aromatic amines
Answer: c

Question: A sequence of how many nucleotides in messenger RNA makes a codon for an amino acid ? 
(a) Three
(b) Four
(c) One
(d) Two
Answer: a