Carbohydrate Digestion Flashcards
The human body can only handle what form of sugar
D- form (dextrose)
Alpha ring structure
hydroxyl group is on the bottom of the ring structure
Beta ring structure
hydroxyl group is on top of the ring structure
glycocitic linkage
OH interacts with another OH or monosaccaride
this is how we get di, oligo, and poly saccharides
Maltose
glucose + glucose
glc-alpha 1-4 glc
sucrose
glucose + fructose
glc-alpha 1-2
lactose
galactose + glucose
glc beta 1-4
Amylose
(starch)
alpha 1-4 glc only
Amylopectin
(starch)
alpha 1-4 glc
Branch point at alpha 1-6
Glycogen
extensively branched
alpha 1-6 glc (more than amylopectin)
Why cant cellulose be digested by animals
Beta 1-4 glc
animals lack cellulase enzyme
What purpsose does cellulose serve
it is an important dietary fiber. Since it is not digested it stretches the intestinal wall to allow more access to food for enzymes
Important heterosaccharides
Hyaluronates Chondrotin 4 and 6 sulfates keratan sulfates dematan sulfates Heparin Heparan sulfates
Proetoglycan
Glycoconjugate with 10% protein and 90% carbohydrate
Glycoprotein
glycoconjugate with 90% protein and 10% carbohydrate
Major portion of carbohydrate in foods
strach
in what form are carbohydrates absorbed by enterocytes (how?)
Monosaccharides via facilitated diffusion
Brush border oligosaccharidases
maltase sucrase isomaltase lactase trehalase (for digestion of mushrooms)
Product of maltase
glucose
Product of sucrase
glucose and fructose
Product of lactase
glucose and galactose
product of trehalse
glucose
Amylase
acts on starch to convert it to oligosaccharide and disaccharide
alpha amylase works on alpha 1-4 glc
glucose and galactose transport
SGLT = Na carrier protein
against the concentration gradient
