Biochemistry Carbohydrate Chemistry and Metabolism

Question 1

Which monosaccharide is the primary fuel for the brain under normal conditions?

Accepted Answer

Glucose

Answer

Fructose

Answer

Galactose

Answer

Ribose

Question 2

The anomeric carbon of glucose is carbon number:

Accepted Answer

C-1

Answer

C-2

Answer

C-3

Answer

C-6

Question 3

Which disaccharide is composed of glucose and fructose joined by an alpha(1→2) glycosidic bond?

Accepted Answer

Sucrose

Answer

Lactose

Answer

Maltose

Answer

Cellobiose

Question 4

Glycogen is the storage polysaccharide in animals. Its branching involves which type of linkage?

Accepted Answer

Alpha(1→4) in chains with alpha(1→6) at branch points

Answer

Beta(1→4) linkages only

Answer

Alpha(1→2) linkages throughout

Answer

Beta(1→3) linkages at branch points

Question 5

The enzyme lactase cleaves lactose into which two monosaccharides?

Accepted Answer

Glucose + galactose

Answer

Glucose + glucose

Answer

Glucose + fructose

Answer

Galactose + fructose

Question 6

Which reaction does hexokinase catalyze in the first step of glycolysis?

Accepted Answer

Glucose → glucose-6-phosphate (using ATP)

Answer

Glucose-6-phosphate → fructose-6-phosphate

Answer

Fructose-6-phosphate → fructose-1,6-bisphosphate

Answer

Glucose → glucose-1-phosphate