Brainscape_Flashcards_CarboMetab
What are carbohydrates primarily used for in the body?
Energy production through oxidation; also structural and communication functions.
Name the 3 main hexose sugars in human biochemistry.
Glucose, Galactose, Fructose.
What are the two main storage forms of carbohydrates?
Starch in plants and glycogen in animals.
Which blood groups are determined by carbohydrate structures?
ABO blood groups.
What makes a sugar a reducing sugar?
A free anomeric carbon that can be oxidized.
Which disaccharide is not a reducing sugar?
Sucrose.
What monosaccharides make up lactose?
Galactose and glucose.
Where is maltose commonly found?
In beer and baby foods as a sweetener.
What are the two glucose polymers in starch?
Amylose and Amylopectin.
How is glycogen different from starch?
It is more highly branched with branches every 8-12 residues.
Why store glucose in polymer form?
For compactness, speed of access, and osmotic inactivity.
What is the function of glycoproteins?
Increase protein solubility, aid folding, protection, and communication.
What are glycosaminoglycans (GAGs)?
Unbranched polysaccharides in mucus and synovial fluid.
What causes mucopolysaccharidoses?
Enzyme deficiencies preventing GAG breakdown.
What enzyme is deficient in Hurler syndrome?
L-iduronidase.
What is the cause of von Gierke’s disease?
Glucose 6-phosphatase deficiency in liver.
What is the cause of McArdle’s disease?
Skeletal muscle glycogen phosphorylase deficiency.
How is glucose absorbed in the gut?
Via Na+-dependent transport using ATP indirectly.
What transporter moves fructose across the intestinal epithelium?
GLUT5.
Why can’t humans digest cellulose?
We lack enzymes to break β-glycosidic bonds.
What is glycolysis?
Breakdown of glucose to pyruvate or lactate, yielding ATP.
Where does glycolysis occur?
In the cytosol.
How many ATP are net gained from glycolysis?
2 ATP per glucose.
What is the first committed step of glycolysis?
Phosphorylation of F-6-P to F-1,6-bisP by PFK-1.
