CARBOHYDRATES

carbohydrates are

sugars with building blocks as monosaccharides

function of carbohydrates

energy source (too much stored will be glycogen → fat), components of cell wall (glycolipids), components of nucleic acids (DNA and RNA), and lipid modification

monosaccharide is the

simplest form of sugar

sugar can be subdivided into 2 categories 

aldehydes (aldose) and ketones (ketose)

empirical formula for aldose and ketose

(CH2O)n

n=3 is the smallest possible sugar

when n = 3 for aldose →

dihydroxyacetone

when n=3 for ketose →

glyceraldehyde

dihydroxy… for aldose draw

okay

glycer… for ketose has 2

isomers L and D which are enantiomers (mirror images)

draw D-erythorose 

okay

draw L-erythrose

okay

draw D-threose

okay

the hydroxyl group on the chiral carbon further away from the functional group determines 

D or L

epimers are a

subgroup of diasteriomers which are sugars that are different in stereochemistry only at a single chiral carbon

epimers are important because

an open chain form is less stable → aldehyde groups open to changes and in order to stabilize it undergoes cyclization to give you the cyclic ring form

the cyclization is between a 

nucleophile (the alcohol) and the carbonyl carbon

draw D glucose chain

okay

draw D mannose

okay

aldehyde + alcohol makes a

hemiacetol

ketone + alcohol makes a 

hemiketal 

explain the cyclization of D glucose

the oxygen on C5 attacks the carbonyl carbon and makes it chiral (the carbon is now called anomeric carbon)

draw when the cyclization occurs in D-glucose

okay

draw what happens when you redox the cyclized D-glucose as alpha and name it and tell its prominence

not as prominent it exists in 1/3 called alpha-D-glucopyranose

draw what happens when you redox the cyclized D-glucose as beta and name it and tell its prominence

most prominent (2/3) called B-D-glucopyranose

the functional group for glucose is and name

aldohexose functional group is aldehyde

D-fructose functional group and name

ketohexose functional group is ketone

draw D-fructose

okay

draw the cyclization of D-fructose

draw the beta form of D-fructose and give the name and prominence 

B-D-fructofuranose (2/3) predominant 

draw the alpha form of D-fructose and give the name and prominence

A-D-fructofuranose

explain the folding purpose

folds to protect the functional group because open chain functional group is more reactive and the cyclized form is more stable

modifications of sugars

only breaks down if ATP is needed so we modify

the modifications of sugars allows cells to 

change properties and functionalities of sugar

the changes to the properties and functionalities of sugar are

phosphorylation and glycosidation

when you phosphorylate the sugar you are

making the sugar more negative/polar (1st step) and make it harder to leave (2nd step) and this triggers glycolysis and keeps glucose in

draw the phosphorylation of glucose

then you can add another Pi 

the sugar chains are ___ agents and you can add in an ____ agent that turns ___

reducing, oxidizing, the aldehyde or the ketone into a carboxylic acid 

the sugar itself is a reducing agent and is called a

reducing sugar

glycosidation is transforming

glucose to glycosides

draw B-D-glucopyranose

glycosidation is when the

acid will protonate the OH group and it turns into a carbocation intermediate where ROH is the nucleophile

draw the glycosidation

okay

the bond between the OCH3 in the carbocation intermediate in glycosidation is called 

O-glycosidic linkage and it is between C1 of glucose and O of alcohol 

phosphodiester bonds mean you have a

fatty acid

disaccharides come from

building blocks of monosaccharides

the disaccharides are

lactose, fructose, and maltose

alpha and beta mean where the hydroxyl group is in 

disaccharides 

lactose is the

milk sugar

lactose is composed of

d-galactose and d-glucose

lactose bond is 

glycosidic bond specifically b-1,4-glycosidic

the b-1,4-glycosidic bond the first number is between

C1 of the first monomer

the b-1,4-glycosidic bond the second number is between

C4 of the 2nd monomer

draw lactose

sucrose is special because

it is a none reducing sugar and will not undergo redox

sucrose is between 

alpha - D-glucose and Beta-D fructose 

what is the bond of sucrose 

alpha - 1,2- glycosidic 

draw sucrose 

okay 

reducing sugars can be

oxidized

maltose is between

2 glucose molecules

the bond for maltose is 

alpha 1,4 glycosidic 

maltose is the backbone for

polysaccharides

draw maltose

okay

the 3 polysaccharides are

glycogen, starch, and cellulose

polysaccharides are broken into

2 categories homopolymer and heteropolymer

glycogen breakdown

energy storage in animals and humans, most common, monomer is glucose, branches (every 10 residues) it is a continuation of maltose, it goes glucose → maltose → glycogen and the linkage is alpha -1,4- glycosidic (for linear chain) and alpha 1,6 glycosidic (when it branches)

glycogen is more 

helical because the amount of branching 

draw the basic bonding structure for glycogen

okay

starch is the energy storage for

plants

starch can be broken down into two types: 

amylose and amylopectin

amylose is the

unbranched alpha 1,4, linkage

amylopectin is the 

branched alpha 1,4 and alpha 1,6 linkage

the backbone for starch is 

glucose 

amylopectin is not as

branched as glycogen it is every 30 or so resides are branched

cellulose is in 

plants 

cellulose linkage is

beta-1,4-glycosidic linkage

cellulose backbone is 

glucose 

cellulose is used for

structure and strength

cellulose dietary fiber is when you

consume food not everything goes at the same rate and speeds up the rate

cellulose is used as a structure because the

beta 1,4 stacks easier than alpha 1,4

draw blood type O order

draw blood type A order

draw blood type B order

triangle in blood type order means

galactose

circle in blood type order means

N-acetyl-glycosamine

square in blood type order means

fructose

pentagon in blood type order means

N-acetyl-galactosamine