Q25Assertion & reason
Label the glucose and fructose units in the following disaccharide and identify anomeric carbon atoms in these units. Is the sugar reducing in nature? Explain. (3)
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C1 of glucose unit and C2 of fructose unit are anomeric carbon atoms in this disaccharide. The disaccharide is non reducing sugar because —OH groups attached to anomeric carbon atoms are involved in the formation of glycoside bond. Distribution of marks • Recognising glucose and (½ mark) fructose units correctly • Identification of anomeric carbon (½ ×2 = 1 mark) • Proper explanation for non reducing nature (1½ marks)