carbohydrate Flashcards
Pentoses of Physiological Importance:
D-Ribose
D-Ribulose
D-Arabinose
S-Xylose
L-Xylulose
Nucleic acids and metabolic intermediate
Structural component of nucleic
acids and coenzymes, including
ATP, NAD(P), and flavin
coenzymes
D-Ribose
Metabolic intermediate
Intermediate in the pentose
phosphate pathway
D-Ribulose
Plant gums
Constituent of glycoproteins
D-Arabinose
Plant gums,
proteoglycans,
glycosaminoglycans
Constituent of glycoproteins
S-Xylose
Metabolic intermediate
Excreted in the urine in
essential pentosuria
L-Xylulose
Hexoses of Physiological Importance
D-Glucose
D-Fructose
D-Galactose
D-Mannose
Fruit juices, hydrolysis of starch, cane or
beet sugar, maltose and lactose
The main metabolic fuel for tissues; ‘blood sugar’
Excreted in the urine (glucosuria) in poorly controlled diabetes mellitus as a result of hyperglycemia
D-Glucose
Fruit juice, honey, hydrolysis of cane or beet sugar and inulin, enzymic
isomerization of glucose syrup
for food manufacture
Hereditary fructose intolerance leads
to fructose accumulation
and hypoglycemia
D-Fructose
Hydrolysis of lactose
Readily metabolized to glucose; synthesized in the mammary gland for
synthesis of lactose in milk, A constituent of glycolipids and glycoproteins
Hereditary galactosemia as a result of failure to metabolize galactose leads to cataracts
D-Galactose
Hydrolysis of mannan gums
Constituent of glycoproteins
D-Mannose
Disaccharides of Physiological Importance
Sucrose
Lactose
Maltose
Isomaltose
Lactulose
Trehalose
Rare genetic lack of sucrase leads to sucrose intolerance-diarrhea and
flatulence
Sucrose
Lack of lactase (alactasia) leads
to lactose intolerance-diarrhea and
flatulence;
may be excreted in the urine in pregnancy
Lactose
Enzymic hydrolysis of starch (amylase);
germinating cereals and malt
Maltose
