UDP glucose is not used in

Glycogen Synthase - The glucose moiety from UDP-glucose is transferred to a glycogen primer (glycogenin) molecule. The primer is essential to accept the glycosyl unit. The primer is made up of a protein-carbohydrate complex. It is a dimeric protein, having two identical monomers. An oligosaccharide chain of 7 glucose units is added to each monomer. Glycogen primer (n)+ UDP-glucose --------- Glycogen (n+1) + UDP In the next step, activated glucose units are sequentially added by the enzyme glycogen synthase. The glucose unit is added to the nonreducing (outer) end of the glycogen primer to form an alpha-1,4 glycosidic linkage and UDP is liberated. GALACTOSE METABOLISM - Galactose is a constituent of lactose of milk sugar, and is taken in the diet. Galactose is not an essential nutrient, because UDP glucose can form UDP galactose. REF: DM VASUDEVAN TEXTBOOK OF BIOCHEMISTRY, SIXTH EDITION,PG.NO.,109,120.