Basic Biochemistry Welcome to your Basic Biochemistry test. 1. Amino acid with three basic functional groups is Lys Arg Glu Asp None 2. Which of the following amino acid does not have ionisable side chain? Asp Glu Tyr Lys None 3. Charged form of amino acids, Is neutral at pH 7 and this form is called as zwitterion Only COOH is ionised at pH 7 and this form is called as zwitterion Only NH3+ group is ionised at pH7 and this form is called as zwitterion Both the groups are ionised at pH 7 and this form is called as zwitterion None 4. Peculiar characteristic of the amino acids is, It can form large number of the conformational variety in the protein structure It acts as acids and also as base It makes protein work under wide range of pH Only 1 1&2 None 5. What is pI value? It is a negative log of the pKa value It is a value of pH where amino acids have net zero charge pH at which all the groups in an amino acid are protonated pH at which the proteins have net positive charge at low pH None 6. The biological properties of the proteins are conferred by Physical properties of the amino acids Chemical properties of the amino acids Surrounding molecules of the proteins Concentration of the proteins in the cytoplasm 1&2 None 7. Number of common amino acids in biological system is 20 27 30 11 None 8. Functionality of the proteins depends on Overall 3-d structure of the protein Chemical properties of the constituent amino acids Intronic sequences All of the above 1 & 2 None 9. Aliphatic groups of the amino acids tend weakly donate the electrons True False None 10. Proteins are formed of one or mode polypeptides. True False None 11. Which of the following is true? pKa values of carboxyl groups in all amino acids are same pKa values of carboxyl groups in the same amino acid are same Neighbouring chemical groups in amino acids influence the pKa value of the group None of the above None 12. Partition coefficient is Ability of the amino acid to interact with the molecules of the support material in chromatographic techniques Relative solubility of the amino acids in the polar and non-polar solvents Ability of the amino acids to dissolve in the water Ability of the amino acids to dissolve in non polar solvents None 13. Paper chromatography separates amino acids based upon Net electrical charge Mass of the molecule 3-D structure of the amino acid pKa values None 14. The difference between the paper electrophoresis and paper chromatography is Electric potential is applied between the two ends of the paper in electrophoresis In paper electrophoresis total charge on the molecule is responsible for the separation In paper chromatography molecules separate on the basis of the partition coefficient All of the above. None 15. Which of the following amino acid is most commonly involved in the disulphide bond formation? Cys Asp Ser Glu None Please fill in the comment box below. Time's up
