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CHEMISTRY MCQs (PART 4)

CHEMISTRY MCQs (PART 4)





128. Physiologically active configuration of amino acids: 
(A) L 
(B) D 
(C) For some amino acids it is either of two 
(D) Neither L nor D

 129. Cystine is synthesized from
 (A) Cysteine 
(B) Methionine 
(C) Arginine
 (D) Leucine

130. The major constituent of the proteins of hair and keratin of skin: 
(A) Arginine 
(B) Cysteine 
(C) Glycine 
(D) Arginine 

131. NH3 is removed from brain mainly by 
(A) Creatinine formation 
(B) Uric acid production 
(C) Urea formation
 (D) Glutamine formation

132. Mechanism by which NH3 is removed from the kidneys is 
(A) Urea formation 
(B) Uric acid formation 
(C) Creatinine formation
(D) None of these

133. Low density plasma proteins are rich in 
(A) Chylomicrons 
(B) Cholesterol 
(C) Triglycerides 
(D) Phospholipids 

134. Transcortins are 
(A) Mucoproteins 
(B) Glycoproteins 
(C) Metalloproteins 
(D) Lipoproteins 

135. Proteins that carries Iron into different tissues is 
(A) Ceruloplasmin 
(B) Trans cortin 
(C) Mucoproteins 
(D) Glycoproteins

136. Naturally occurring amino acids have 
(A) L-Configuration 
(B) D-Configuration 
(C) DL-Configuration 
(D) None of these 

137. Abnormal chain of aminoacids in sickle cell anemia is 
(A) β-chain 
(B) β-chain 
(C) γ-chain 
(D) r-chain

138. A dietary deficiency of tryptophan and nicotinate leads to
 (A) Beri Beri 
(B) Xerophthalmia 
(C) Anemia 
(D) Pellegra 

139. Which one of the following is an essential amino acid? 
(A) Arginine 
(B) Tyrosine 
(C) Phenylalanine
 (D) Proline 

140. One of the following amino acid is solely ketogenic: 
(A) Lysine 
(B) Alanine 
(C) Valine 
(D) Glutamate

141. Along with CO2, NH3 and ATP, the amino acid that is needed in urea cycle is 
(A) Alanine 
(B) Isoleucine
 (C) Aspartate 
(D) Glycine 

142. Isoelectric pH of an amino acid is that pH at which it has a 
(A) Positive charge 
(B) Negative charge 
(C) No charge 
(D) None of these 

143. Which of the following contributes nitrogen atoms to both purine and pyrimidine rings? 
(A) Aspartate 
(B) Carbamoyl phosphate 
(C) CO2 
(D) Glutamine 

144. Which amino acid is a lipotropic factor? 
(A) Lysine 
(B) Lecuine 
(C) Tryptophan 
(D) Methionine

145. Which of the following protein is rich in cysteine? 
(A) Elastine 
(B) Collagen 
(C) Fibrin 
(D) Keratin

146. Which amino acid is present at 6th position of β-chain of Hbs instead of glutamate in HbA?
 (A) Cysteine
 (B) Valine
 (C) Aspartate
 (D) Glutamate

147. The amino acid which contains an indole group is 
(A) Histidine 
(B) Arginine 
(C) Cystine 
(D) Tryptophan

148. From two amino acids peptide bond formation involves removal of one molecule of 
(A) Water 
(B) Ammonia 
(C) Carbondioxide 
(D) Carboxylic acid 

149. Polymers of more than 100 amino acids are termed 
(A) Proteins 
(B) Polypeptides 
(C) Both (A) and (B) 
(D) None of these 

150. The example of globulins: 
(A) Leucosin 
(B) Tuberin 
(C) Oryzenin 
(D) Legunelin 

151. The example of scleroproteins: 
(A) Glutamin 
(B) Giladin 
(C) Salmine 
(D) Elastin 

152. The example of phosphoprotein: 
(A) Mucin 
(B) Ovovitellin 
(C) Ovomucoid 
(D) Tendomucoid

153. The example of metalloproteins: 
(A) Siderophilin 
(B) OREES mucoid 
(C) Elastin
 (D) All of these

154. The example of chromoprotein: 
(A) Salmine 
(B) Catalase
(C) Zein 
(D) Gliadin 


155. Deamination is ______ of amino group. 
(A) Removal 
(B) Addition 
(C) Supplementation
(D) None of these 


156. Proteins produce polypeptides from proteins by 
(A) Oxidizing 
(B) Reducing 
(C) Hydrolyzing 
(D) None of these 


157. Proteins react with biuret reagent which is suggestive of 2 or more 
(A) Hydrogen bonds 
(B) Peptide bonds 
(C) Disulphide bonds 
(D) Hydrophobic bonds

158. The disulphide bond is not broken under the usual conditions of 
(A) Filtration 
(B) Reduction 
(C) Oxidation 
(D) Denaturation 

159. Insulin is oxidized to separate the protein molecule into its constituent polypeptide chains without affecting the other part of the molecule by the use of 
(A) Performic acid 
(B) Oxalic acid 
(C) Citric acid 
(D) Malic acid 

160. Each hydrogen bond is quite 
(A) Weak 
(B) Strong 
(C) Both (A) and (B) 
(D) None of these

 161. A coiled structure in which peptide bonds are folded in regular manner by 
(A) Globular proteins 
(B) Fibrous proteins 
(C) Both (A) and (B) 
(D) None of these

 162. In many proteins the hydrogen bonding produces a regular coiled arrangement called 
(A) α-helix 
(B) β-helix 
(C) Both (A) and (B) 
(D) None of these

 163. Many globular proteins are stable in solution although they lack in 
(A) Hydrogen bonds 
(B) Salt bonds 
(C) Non-polar bonds 
(D) Disulphide bonds

 164. Each turn of α-helix contains the number of amino acids 
(A) 2.8 
(B) 3.2 
(C) 3.4
(D) 3.6 

65. The distance travelled per turn of α-helix in nm is 
(A) 0.34 
(B) 0.44 
(C) 0.54 
(D) 0.64 

166. α-helix is disrupted by certain amino acids like
 (A) Proline
 (B) Arginine
 (C) Histidine
 (D) Lysine 

167. α-helix is stabilized by 
(A) Hydrogen bonds 
(B) Disulphide bonds 
(C) Salt bonds 
(D) Non-polar bonds 

168. Foetal haemoglobin contains 
(A) Two α and two γ chains
(B) Two β and two γ chains 
(C) Both (A) and (B) 
(D) None of these 

169. When haemoglobin takes up oxygen there is a change in the structure due to the moving closer together of 
(A) β-chains 
(B) β-chains 
(C) γ-chains 
(D) α and γ chains 

170. The hydrogen bonds in the secondary and tertiary structure of proteins are directly attacked by (A) Salts 
(B) Alkalies 
(C) Detergents 
(D) All of these

 171. The hydrogen bonds between peptide linkages are interfered by 
(A) Guanidine 
(B) Uric acid 
(C) Salicylic acid 
(D) Oxalic acid

 172. The digestability of certain denatured proteins by proteolytic enzymes 
(A) Decreases 
(B) Increases 
(C) Normal 
(D) None of these

 173. The antigenic antibody functions of proteins by denaturation are frequently 
(A) Not changed 
(B) Changed 
(C) Both (A) and (B)
(D) None of these 

174. In case of severe denaturation of protein, there is 
(A) Reversible denaturation 
(B) Moderate reversible denaturation 
(C) Irreversible denaturation 
(D) None of these 

175. When egg albumin is heated till it is coagulated, the secondary and tertiary structures of the proteins are completely lost resulting in a mixture of randomly arranged 
(A) Dipeptide chains 
(B) Tripeptide chains 
(C) Polypeptide chains
(D) All of these

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