1 Explain the meaning of the term mutarotation.

2 Draw the structure of a disaccharide made up of two D-glucoseunits. The glycosidic bond is

    α-1,6-glycosidic bond.

3 Trehalose is a disaccharide that can be obtained from fungi,sea urchins and insects. Acid hydrolysis of

    trehalose yields only D-glucose. Trehalose ishydrolysed by α-glucosidase and not by β-glucosidase

    enzymes. Methylation of trehalose followed byhydrolysis yields two molar equivalents of

    2,3,4,6-tetra-O-methyl-D-glucopyranose.

1.   From the following experimental data, deduce thestructure of trehalose.
2. What will be the effect of trehalose on Fehling’ssolution?

4(a) Suggest a test you will use to show that a given foodsubstance contains protein.

1. Show how you will use

1. Modified Gabriel’s Synthsis
2. Streckers’s Synthesis   to prepare phenylalanine inthe laboratory.

5 (a) Describe in detail how you will determine the primarystructure of protein.

(b) You have been given a mixture of lysine, histidine andcysteine. The isoelectric point of the amino acids are asfollows:

Histidine                       7.64

Lysine                            9.74

Cystenie                        5.02

Show how you will separate the mixtureinto the pure forms. State and describe any instrument that youwill use to separate the components in the mixture.

6 (a) A decapeptide has the following amino acidcomposition:

         Ala₂, Arg, Cys, Glu, Gly, Leu, Lys, Phe, Val

       Partial hydrolysis yieldsthe following tripeptides:

       Cys-Glu-Leu + Gly-Arg-Cys +Leu-Ala-Ala+ Lys-Val-Phe + Val-Phe-Gly.

       Reaction of the decapeptidewith 2,4-dinitrofluorobenzene yields 2,4-dinitrophenylysine. Fromthe

       experimental data, deducethe primary structure of the decapeptide.

   (b) Suggest a scheme you will follow to synthesizethe dipeptide Ala-Gly