Metabolism Flashcards
What are the four classes of carbohydrates?
Monosaccharides
Disaccharides
Oligosaccharides
Polysaccharides
How can monosaccharides be classified?
Number of carbon atoms (triose, tetrose, pentose, hexose)
Isomer (D- or L-isomer)
In which isomeric form are most important sugars?
D-isomers
What is an isomer?
The same atoms but bonded together in a different 3D arrangement
What do glucose, fructose and galactose have in common?
They are all hexoses (6 carbons) which different arrangements of the same atoms
What do pentoses and hexoses normally form?
Cyclic molecules
Pentose - 5 membered rings
Hexoses - 6 membered rings
Name 2 important pentose monosaccharides
Ribose
Deoxyribose
Name 3 important hexose monosaccharides
Glucose
Galactose
Fructose
Name 4 important polyoligosacchardies
Starch
Cellulose
Glycogen
Dextrin
What is starch?
Branched polymer of glucose.
Formed either by a-1,4 (and) a-1,6 glycosidic bonds
What is cellulose?
Linear polymer of glucose
What is glycogen?
Extensively branched polymer of glucose
What is dextrin?
Branched oligomer of glucose
Breakdown product of starch and glycogen
What are the four main types of biologically important lipids?
Fatty acids
Triglycerides
Cholesterol
Cholesterol esters
What are fatty acids?
Hydrocarbon chains of various lengths
Name 2 differences between saturated and unsaturated fatty acids
Saturated
No double bonds between C atoms
Solid at room temperature
Unsaturated
At least one double C bond
Liquid at room temperature
What makes a triglyceride?
1 Glycerol
3 Fatty acid chain
Describe cis and trans fatty acids
Applies to unsaturated fat
Movement around the double C bond
Describe cis fatty acid
Loosely packed together, causes fatty chain to ‘kink’
Remember cis like cissy - floppy wrist, kink, 2 C,s 2 of the same
Describe trans fatty acid
Tightly packed together, chain continues on
What is a phospholipid?
A phosphate group attached to one or more fatty acid chains
How are phosphate groups attached to fatty acid chains?
Via glycerol or sphingosine
What is a glycolipid?
Carbohydrate (oligosaccharide) attached to one or more fatty acid chains
How are phosphate groups attached to fatty acid chains in modified lipids?
Via glycerol or sphingosine