Carbohydrates Flashcards
What must a sugar contain?
C H O
Aldehyde/ketone group, along with 1 or more hydroxy groups
Stereochemistry
What makes a molecule D or L
D- oh on the right( one above the last ch20h)
L -oh on the left
What is the predominant sugar, and why?
Glucose (cyclic form), constant equilibrium in the body which changes glucose (linear) to cyclic.
Cyclic forms are more stable
How is cyclic glucose soluble
Contain many hydroxyl groups that readily form h honds
What is a hemiacetal
Contains carbon with a free oh and on OR group
Anomeric carbons
What’s the difference between alpha and beta anomers
A-oh group below plain of ring
B- oh group above plain of ring
What is a disaccharide
2 monomers which connect to form a dimer, by a glycosidic bond.
Why are 6 and 5 member rings the most stable
Carbon has sp3 configurations, which requires angle of atoms at 109° which makes it most stable
A- anomers and B-anomers (digestion)
Alpha- Readily digested in the body! (Why we need sugar in diet to retain level of alpha anomers)
How are sugars used as laxatives
No biological effect ( doesn’t interact with receptors) but changes the way water is absorbed in the bowel ( increase sugar concentration)
Causes water to accumulate in colon=softens stools
How are sugars used in phase 2 metabolism
What is glucose converted into?
Drugs are conjugated to make the molecule more water soluble to be excreted in urine
Glucose converted into carboxylic acid( make more water soluble) which also makes a salt with the drug and makes it more soluble
Uses of sugars
Amino sugars- used in joint health, and in antibiotics to treat bacterial infection (gentamiein)
Glycolipids- proteins phosphorylise with sugar on surface of membranes and it used in cell recognition
