Flashcards
Carbohydrates
Cards in this deck (32)
- 1Carbohydrates (Sugars)- most abundant biomolecule
- important to energy metabolism
- essential components of nucleic acids - 2Monosaccharidescombine a carbonyl (C=O) group (either an aldehyde or ketone) and at least 2 carbons bearing hydroxyl (alcohol) groups (C-OH)
- 3Triosethe simplest monosaccharides containing 3 carbon atoms (e.g. glycerol and acetone)
- 4Emil Fischer- German chemist who studied analysis, synthesis and stereochemistry of simple sugars
- contributed to much of our understanding of carbohydrate chemistry - 5Enantiomers- mirror images that differ in configuration at every chiral carbon atom (commonly called left-handed or right-handed forms of a molecule)
- identical chemical properties but differ in optical activity - 6Diastereomers- stereoisomers that differ in handedness at some carbon atoms but not at others
- do not have identical chemical properties because spatial relationships among atoms are different - 7Most naturally occuring sugars are ___ sugars.D-sugars
- 8Epimerspair of sugars that are identical except for the configuration at one carbon atom
- 9In D-sugars, every time a C atom is added, the number of isomers _________.doubles
- 10Aldehydes can react with alcohols to produce _____________.hemiacetals
- 11Ketones can react with alcohols to produce _____________.hemiketals
- 12The (1) ____ group at C-5 reacts with the (2) ________ of the aldehyde group to form a stable 6-membered ring.(1) OH
(2) carbonyl carbon - 13Anomersisomeric forms of stereoisomers that differ only in their configuration around the hemiacetal or hemiketal carbon
- 14In the cyclization of an aldose or ketose, the (1) (electrophilic/nucleophilic) carbonyl atom reacts with the (2) (electrophilic/nucleophilic) O of an OH group.(1) electrophilic
(2) nucleophilic - 15Mutarotation- solid glucose is found either in the α or the β form of the hemiacetal
- When dissolved in water, it slowly converts into an equilibrium mixture of the α, β and linear forms - 16When sugars cyclize, they form what two ring forms?- pyranose (6-membered ring)
- furanose (5-membered ring) - 17Glycosidethe anomeric carbon atom of a sugar in a glycoside is electrophilic, making it reactive — it is at this position that most reactions involving ring forms of sugars take place
- 18Reducing Sugar- any sugar that is capable of acting as a reducing agent because it has a free aldehyde group or a free ketone group
- all monosaccharides are reducing sugars, along with some disaccharides, oligosaccharides, and polysaccharides - 19Non-Reducing Sugar- some sugars that don’t react with oxidants (e.g. sucrose)
- if the anomeric carbon is involved in a glycosidic bond (can't react) - 20The oxidation of sugars by Cu2+ only occurs with the ________ form.linear (which exists in equilibrium with cyclic forms)
- 21Glycosidic BondC-O bond
- 22Glycosilic BondC-N bond
- 23Disaccharides- glycosides formed when two monosaccharides are linked through a glycosidic bond
- occurs when the anomeric carbon of one sugar reacts with the OH group of another - 24Reducing Endin disaccharides and polysaccharides, the end of a chain with a free anomeric carbon (one not involved in a glycosidic bond)
- 25Galactose and glucose are _______ ___________ of lactose.structural isomers
- 26Maltose- formed in malted grain by the breakdown of starch
- reducing sugar - 27Trehalose- found in many foods, notably mushrooms
- non-reducing sugar - 28Polysaccharides- polymers of monosaccharide units
- most carbohydrates found in nature occur as polysaccharides
- often highly branched (several OH groups) - 29Homopolysaccharidesmade from a single type of sugar monomer
- 30Heteropolysaccharidesmade from two or more kinds of sugar subunits
- 31Glucansglucose homopolymers
e.g., starch (plants), glycogen(animals)
cellulose, chitin - 32Mannansmannose homopolymers
Information
- Description
- 2 BIOC*2580 (Exam Review) Flashcards on Carbohydrates, created by Erin Martin on 13/04/2016.
- Created by
- Erin Martin
- Views
- 4
- History
-
- Created by Erin Martin · Apr 13, 2016
- Copied by Erin Martin · Apr 13, 2016
- Rating