Carbohydrates Flashcards
combination of lec and lab ppts
major energy sources
Carbohydrates
Sugars linked by glycosidic bonds
Oligosaccharides
Monosaccharide containing a ketone group
as part of its structure
Ketose
- Compounds that contain a single carbonyl group and two or more hydroxyl groups
- Cannot be hydrolyzed to simpler carbohydrates
- Have the general formula Cn(H2O)n
Monosaccharides
Formed when many monosaccharides are bonded together
Polysaccharides
Building blocks of all carbohydrates
Monosaccharides
Essential structural components of several classes of organisms
Polysaccharides
Play a key role in processes that take place on the surfaces of cells, such as cell–cell interactions and immune recognition
Oligosaccharides
Simplest carbohydrate that contains a chiral carbon; Exists in two isomeric forms that
are mirror images of each other
Glyceraldehyde
Simplest monosaccharide that contains
three carbon atoms
Triose
Monosaccharide containing an aldehyde
group as part of its structure
Aldose
Molecules that differ from each other only in their configuration
Stereoisomers (optical isomers)
Does not contain a chiral carbon atom; Does not exist in non-superimposable mirror-image forms
Dihydroxyacetone
Three-dimensional arrangement of groups around a chiral carbon atom
Configuration
Mirror-image, non-superimposable stereoisomers
Enantiomers
T or F: Possibility of stereoisomerism increases as the number of carbon atoms decrease
False - carbon atoms increases
Two-dimensional representations of the
stereochemistry of three-dimensional molecules
Fischer Projections
—OH is on the right of the highest-numbered chiral carbon
D configuration
—OH is on the left of the highest-numbered chiral carbon
L configuration
Non-superimposable, non–mirror-image stereoisomers
Diastereomers
Compound that is formed by the reaction of
an aldehyde with an alcohol
Hemiacetal
Diastereomers that differ from each other in the configuration at only one chiral carbon
Epimers
Compound that is formed by the reaction of
a ketone with an alcohol
Hemiketal
Cyclic sugar with a five-membered ring; Rings are very nearly planar
Furanose
carbonyl carbon becomes a chiral center is called?
anomeric carbon
Cyclic form of a sugar containing a six-
membered ring; Rings exist in solution in the chair conformation
Pyranose
—OH on the anomeric carbon is cis to the terminal —CH2OH
B-
trans designation
a-
Intermediates in the breakdown of carbohydrates to provide energy
Phosphate esters
Compound formed when a hemiacetal
carbon reacts with an alcohol to give a full acetal
Glycoside
Resulting bond in glycoside is called
glycosidic bond
Glycosides involving a furanose
Furanosides
Glycosides involving a pyranose
Pyranosides
Sugars with a substituted amino group (—NH2) as part of its structure
Amino Sugars
Common table sugar, which is obtained from the juice of sugarcane and sugar beets
Sucrose
formed when glucose and fructose are
bonded together
Disaccharide
Made up of β-D-galactose and D-glucose
Lactose
Group at the anomeric carbon of the glucose
portion is not involved in the glycosidic linkage
Reducing sugar
Disaccharide that is obtained from the hydrolysis of starch
Maltose
this is found in milk
Lactose
Polymers of sugars
Polysaccharides
this is obtained from starch
Maltose
Major structural component of plants, especially of wood and plant fibers
Cellulose
Polymer consisting of only one type of monosaccharide
Homopolysaccharide
Polymer consisting of more than one type of
monosaccharide
Heteropolysaccharide
Component of the vitreous humor of the eye and of the lubricating fluid of joints
Hyaluronic acid
Branched chain polymer, with branches starting at α(1 → 6) linkages along the chain of α(1 → 4) linkages
Amylopectin
Linear polymer of glucose, with all the residues linked together by α(1 → 4) bonds
Amylose
From chicken liver; Branched-chain polymer of α-D-glucose; Consists of a chain of α(1 → 4) linkages with α(1 → 6) linkages at the branch points
Glycogen
Protein situated at the heart of every glycogen
Glycogenin
In cellulose, the monomer is ______
β-D-glucose
Type of polysaccharide based on a repeating
disaccharide
Glycosaminoglycans
n chitin, the monomer is ___________
N-acetyl-β-D-glucosamine
Major structural component of the exoskeletons of invertebrates, such as insects and crustaceans
Chitin
Major components of bacterial cell walls
Heteropolysaccharides
Polysaccharide that contains peptide crosslinks; Found in bacterial cell walls
Peptidoglycan
Polymer made up of D-galacturonic acid, which is a derivative of galactose in which the hydroxyl group on C-6 has been oxidized to a carboxyl group; Found in plant cell walls
Pectin
Major nonpolysaccharide component in plant cell walls; Polymer of coniferyl alcohol
Lignin
Components of connective tissue
Chondroitin sulfates and keratan sulfate
Stereoisomers that differ in configuration only at the anomeric carbon are called
anomers
A five- or six-membered cyclic hemiacetal is represented as a planar ring, lying roughly perpendicular to the plane of the paper
Haworth Projections
Glycoproteins with a high carbohydrate content
Proteoglycans
Play an important role in eukaryotic cell
membranes
Glycoproteins
a- means that the –OH on the anomeric carbon is on the side of the ring _____ from the
terminal –CH2OH
opposite
The prefix “deoxy” means
“without oxygen”
B- means that the –OH on the anomeric carbon is on the _____ side of the ring as the terminal – CH2OH
same
A six-membered hemiacetal ring is called
pyranose
a five-membered hemiacetal ring is called
furanose
The change in specific rotation that accompanies the equilibration of a- and b-anomers in aqueous solution
Mutarotation
A cyclic acetal derived from a monosaccharide is called
glycoside
The bond from the anomeric carbon to the –OR group is called
glycosidic bond
The reduction product is called
alditol
found in the plant world in many berries and in cherries, plums, pears, apples, seaweed, and algae
Sorbitol
T or F: Alditols are named by changing the suffix -ose to -itol
True
a linear polysaccharide of D-glucose units joined by b-1,4- glycosidic bonds
Cellulose
act like stiff rods and align themselves side by side into well-organized water-insoluble fibers in which their –OH groups form numerous
intermolecular hydrogen bonds
Cellulose molecules
the oxidation product is called
aldonic acid
a group of polysaccharides that contain carboxyl groups and/or sulfuric ester groups, and play important roles in the structure and function of connective tissues
Acidic polysaccharides
synthesized and stored in mast cells of various
tissues, particularly the liver, lungs, and gut
Heparin
best known and understood of its biological functions is its anticoagulant activity
Heparin
it binds strongly to antithrombin III, a plasma protein involved in terminating the clotting process
Heparin