Carbohydrates Flashcards
(41 cards)
What are carbohydrates (Biological answer)
An important class of molecules involved in a variety of biological processes
What are carbohydrates (Chemical answer)
A molecule containing carbon, hydrogen and oxygen atoms
What’s the molecular formula of a carbohydrate
Cm(H2O)n
What does the M mean in the molecular formula
That the n number is more or equal to 3
What is a way to capture energy and direct it where its required
Fixation of CO2
How are monosaccharides classified
based on open form according on size of carbon skeleton
How is a monosaccharide classified on its C=O group
ketone - ketohexose
aldehyde - aldohexose
What must a monosaccharide contain in it’s stereochemistry
Chiral carbon
In the R and S system which is referred to L and D
R=D
S=L
Where does the numbering start
On the aldehyde/ketone side of the main carbon chain
Enantiomer
complete mirror image
what’s a diastereomer
At least one stereo centre has a different configuration
What’s an epimer
Only one chiral centre has a different configuration
What can sugars form in open form
Furanose and Pyranose rings
The introduction of an extra chiral centre is also known as
Anomeric carbon
What does equiliibrium in solutions depend on
Steric clashes
Equillibrium between open and cyclic forms is called what
mutarotation
Why in monosaccharides is the cyclic form less biologically relevant
due to both forms being interconverted via the open form
What’s a disaccharide
Two monosaccharides joined together via glycosidic linkage
How are disaccharides formed
By a dehydration or condensation reaction
in disaccharides beta or alpha linkage is determined by
The configuration of the left anomeric carbon
What’s a polysaccharide
same as disaccharide but repeated units
What do polymers differ by
monomer unit
type of glycosidic link
linear vs branched and degree of branching
List examples of polysaccharides
glycogen
cellulose
chitin
amylose and amylopectin
