| A | B |
|---|
| what do carbohydrates contain? | contain Carbon, Hydrogen and Oxygen |
| What is the general formula for Carbohydrates? | Cx(H20)Y |
| all carboydrates have what functional groups? | C=O and -OH |
| How are carbohydrates classified?(4 things) | 1. Size of base carbon chain 2. number of sugar units 3.location of C=O 4. Stereochemistry |
| Monosacharides are? | a single sugar unit |
| Disaccharides are? | two sugar units |
| Oligosaccharides are? | 3 to 10 sugar units |
| Polysaccharides are? | more than 10 units |
| chaining of carbohydrates relies on what? | bridging of oxygen atoms (glycoside bonds) |
| The formula for a sugar is? | C6H12O6 |
| What does an aldose have? | A -CHO group |
| What does a ketose contain? | A -CH2OH group |
| how many carbons are in a triose? | 3 |
| how many carbons are in a tetrose? | 4 |
| how many carbons are in a pentose | 5 |
| how many carbons are in a hexose | 6 |
| what are the two monosaccaride classifications? | aldose and ketose |
| When naming carbohydrate what comes first | the monosaccharide prefix ( either aldo or keto) |
| In naming carbohydrates what comes second? | the name for the number of carbon chains (triose/tetrose etc.) |
| the final part to naming a carbohydrate is what? | adding sugar to the end of the monosaccaride prefix and carbon chain suffix |
| what does stereochemistry study? | the spatial arrangement of molecules |
| Stereoisomers have? (3 things) | 1. the same order and types of bonds 2. different spatial arrangements 3. different properties |
| what is a common chemical that exists as a stereoisomer | sugars |
| enantiomers are? | pairs of stereoisomers |
| enantiomers are designated by what two letters at the start of a name? | D- or L- |
| can enantiomers be overlapped? | they are mirror images, they cant be overlapped |
| enantiomers have what in the center? | a chiral center |
| what is an asymmetric carbon? | a carbon that has four different things attached to it |
| What must you have to have stereoisomers | you must have at least one asymmetic carbon |
| what is optical activity? | the ability to rotate plane polarized light |
| what is dextrorotary | rotating right, uses + symbol and usually D- isomers |
| what is levorotary | rotate left, uses - symbol, usually l-isomers |
| what is plane polarized light? | light is passed through a polarized filter, a solution of optical iosmer will rotate the light one direction |
| stereochemistry uses what for 3d drawings | Fischer Projections |
| Fischer projections are always made for what types of carbons? | tetrahedral |
| a horizontal bond to an asymmetric bond designates what in a Fischer projection? | the front plane of the page |
| Vertical bonds designate what in a Fischer projection? | behind the plane of the page |
| D-glyceraldehyde | simplest carbohydrate |
| D-glucose | Most important in diet |
| D-fructose | sweetest of all sugars |
| D- galactose | part of milk sugar |
| D-ribose | used in RNA |
| D-glyceraldehyde is what kind of sugar? | aldotriose |
| look at the position of the alcohol group | if its on the right its D, if its on the left its L |
| glucose is what kind of sugar? | aldohexose |
| The -CH2OH group will always be at the top for what ring to form? | D |
| The -CH2OH group will always be at the bottom for what ring to form? | L |
| hemiacetal | forms from alcohol and aldehyde |
| hemiketal | forms from alcohol and ketone |
| Intramolecular Cyclization | a hemiacetal or hemiketal will form between the carbonyl and the secondary alcohol that is farthest away |
| In intramolecular cyclization what is formed | A new OH group is formed and the O from the carbonyl and the H from the orignal OH |
| anomer | the OH group that is formed can be above or below the ring resulting in two forms |
| in alpha anomers... | OH group is down compared to CH2OH (trans) |
| in beta anomers.... | OH group is up compared to CH2OH (cis) |
| amutarotation | the alpha and beta forms are in equilibrium so one form can convert to another |
| What kind of projections can be used to help see alpha and beta orientations | Haworth projections |
| Furanose rings have how many members, and where is the O located? | the are 5 member rings, and the O is located in the back |
| pyranose is a how many member ring, and the O is located where? | a 6 member ring, and the O is on the back right |
| D-fructose is what kind of sugar? | a ketohexose |
| Can cyclization of D-fructose occur? | yes, the process occurs in ketose sugars |
| D-galactose can be found in other systems t/f | false |
| D-galactose is one half of what? and can it be used directly? | it is one half of lactose and we cannot use it directly |
| D-ribose is used as? | it is part of the backbone of RNA, and the sugar is not used as an energy source |
| When C-2 OH is removed from a D-ribose the sugar becomes what? | deoxyribose |
| Deoxyribose is used as the backbone to what? | DNA |
| Phosphate esters what are they? | the alcohol groups of carbohydrates are able to form esters, the common type is a phosphate ester which is an important carbohydrate for metabolsim |
| A alpha glycosidic bond is what? | a linkage between a C-1 alpha OH and a C-4 OH |
| A beta glycosidic bond is what? | A linkage between a C-1 Beta OH and a C-4 OH |
| Which way does C-4 end ? | It can end up or down depending on the orientation of the monosaccharide |
| What are glycosidic bonds? | The general format used to describe a bond (OH type (alpha or beta) then carbon # of first sugar, carbon # of second sugar) |
| Beta maltose is what? | malt sugar, its not ccommon in nature except in germinating grains |
| what are uses for B maltose? | its an ingredient in infant formulas, production of beer, and flavoring- fresh baked aroma |
| maltose + H2O | 2 glucose |
| What is cellobiose | Like maltose, it is composed of two molecules of D-glucose but with a beta 1-4 linkage |
| is cellobiose stable or unstable? | unstable |
| we lack enzymes that can do what? | hydrolyze cellobiose |
| What must galactose be covnerted to in order for us to use it? | a form of glucose |
| Galactosemia | absence of needed enzymes needed for conversion |
| Build up of what causes toxic effects? | galactose or a metabolic dulcitol |
| not having enzymes to covert galactose can cause what three things to occur? | 1. retardation 2. cataracts 3. death |
| what is lactase? | an enzyme required to hydrolyze lactose |
| lactose intolerance | lack or insufficient amount of the enzyme |
| what is sucrose? | table sugar, common in all plants |
| Aldehyde sugars are what so that they will react with what? | they are readily oxidized, so they can react with Benedict's reagent |
| what other monosaccharide can rearrange in order to give a positive test? | ketose monosaccharides |
| storage polysaccharides | energy storage- starch and glycogen |
| structural polysaccharides | used to provide protective walls or lubricative coating to cells |
| structural peptidoglycans | bacterial cell walls (peptide cross links provide extra strength) |
| starch | energy storage used by plants, chains up to 4000 units |
| amylose | straight chain |
| amylopectine | branched structure and a major part of starch |
| amylose starch | a straight chain that forms coils |
| Amylopectin starch | has side chains, otherwise is like amylose |
| how do you test for starch? | iodine reacts with it to form a blue substance |
| glycogen is what? | energy storage in animals, it is stored in liver and granukes and is similar to amylopectin |
| what is the most abundant polysaccaride? | cellulose which is used in plant structures |
| Mucopolysaccharides | provide a thin, viscous, jelly like coating on cells (most abundant hyaluronic acid) |
| glycoproteins are what and have what biological functions (4)? | proteins that carry covalently bound carbohydrate units 1. immunological protection 2. cell-cell recognition 3. blood clotting 4. interaction with other chemicals |
| Carbohydrates account for what percent of the total weight of a glycoprotein | 1-30% |
| there are two types of glycoprotein structures, what are they and what do they do? | they link sugars to proteins type 1: O- bonds use hydroxyl groups of serine and threonine and N-bonds use side chains of amide nitrogen asapragine |
