Carbohydrates Flashcards
What are carbohydrates made up of
C, H, O
What is the general formula for Carbohydrates
Cn (H2O)n : N=(3-9)
What are 4 common dietary carbohydrates
Starch, Sucrose, Dietary fiber, and Lactose
What is the nutritional reservoir of CH in plants
Starch
Starch is a polysaccharide of
Glucose
What is amylose
unbranched form of starch
What is amylopectin
The branched form of starch
natural sweetener and found in fruits and vegetables
Sucrose
Sucrose is a disaccharide of ___ and ____
glucose and fructose
What is the origin of dietary fiber
plants
A major dietary carbohydrate of animal origin
Lactose
Lactose is a disaccharide of ____ and _____
glucose and galactose
What is the simplest form of carbohydrates
Monosaccharides
What are some examples of monosaccharides
Glucose, fructose, galactose, ribose
What are two monosaccharides
Disaccharides
Maltose, lactose, and sucrose are all
disaccharides
Glycolipids and glycoproteins are
oligosaccharides
what are oligosaccharides
3-10 monosaccharides
What are polysaccharides
> 10 monosaccharides
Glycogen, starch, and cellulose are all
polysaccharides
what are epimers
diastereomers that differ in configuration of only one stereogenic (chiral) center
D-glucose and D-Galactose are examples of
epimers
What three components will help to identify a monosaccharide
Carbon number
Functional group
Stereoisomer form
What are the smallest monosaccharides
3 carbon atoms (triose)
dihydroxyacetone
D and L- glceraldehyde
The D and L nomenclature of a monosaccharide is determined by
position of the OH group farthest from carbonyl carbon
Most sugars are in _____ series in humans
D
Constitutional isomeers
differ in the order of attachment of atoms
Enantiomers
Nonsuperimposable mirror images
What are two forms of diastereoisomers
Epimers
Anomers
What are anomers
differ at new asymmetric carbon upon ring closure
ex. alpha-D-glucose and beta-D-glucose
What are epimers
differ at one of several asymmetric carbons
ex. D-Glucose and D-mannose (or D-galactose)
Diastereoisomers
isomers that are not mirror images
How is a pyranose formed
mutarotation of D-Glucose leads to ring closure
How is a furanose formed
mutarotation of D-Fructose leads to ring closure
What is the the preferred form alpha-D-Glucopyranose or beta-D-Glucopyranose
Beta-D-glucopyranose
What is the difference between an alpha anemia and a beta anomer
The alpha anomer is on the opposite side of the ring as the Ch2OH
The beta anomer is on the same side of the ring from the CH2OH
In solution monosaccarides mostly exist as
ring structure
Does fructose form both pyranose and furanose rings
yes (pyranose from predominates in fructose that is free in solution, and the furanose form predominates in many fructose derivatives)
Deoxyaldose
is a chemically modified monosaccharide derivative
it is a major component of DNA
Acetylated amino sugars
chemically modified monosaccharide derivative
They are components of glycoproteins and glycolipids (cell signaling, cell adhesion, immune response)
Acidic sugars
Chemically modified monosaccharide derivatives
glycosaminoglycans and proteoglycans.
present in cell membrane and in the extracellular matrix
Sugar esters
Chemically modified monosaccharide derivative
constituted the gangliosides in oligodendrocyte of the nervous system
Sugar alcohols (e.g. mannitol, sorbitol, xylitol)
Chemically modified monosaccharide derivatives
food additives, gains importance in uncontrolled diabetes leading to cataracts and peripheral neuropathy used in synthesis of lipids
sucrose shows what kind of linkage
1-2-glycosidic linkage
Lactose demonstrates what kind of linkage
1-4 glycosidic linkage
Maltose demonstrates what kind of linkage
1-4 glycosidic linkage
starch amylose is a polysaccharide of glucose residues linked with
alpha 1,4-glycosidic bonds
Amylopecin is amylose with the addition of
alpha 1,6 glycosidic branch points
Cellulose unbranched polymer of glucose residues joined by
Beta-1,4 linkages
Starch and glycogen use what kind of linkage
alpha 1,4-glycosidic linkages, these are bent and better for storage
O-linkage uses the oxygen on
Serine
N-linked glycosidic bonds uses the N on the
Asn
The first sugar added to an o-linked glycosidic bond is always
xylose
Types of Glycoaminoglycans
Chondroitin sulphate
Dermatan sulphate
Heparan sulphate
Keratan sulfate
