Macromolecules- carbohydrates
Learning outcomes
1. List the main features of carbs
2. Explain the difference between types of isomer
3. Describe the formation of glycosidic bonds
4. Outline the role of carbs in nature
Carbohydrates
Also called saccharides
Compounds formed from carbon, hydrogen and oxygen
1:2:1 ratio
Formula (CH2O) n, n=number of carbon-hydrate groups
Ready source of energy
C-H covalent bonds hold much energy
Good energy storage molecules
Sugars, starch glucose
Other crabs are structural- cellulose lignin chitin in cell walls
Monosaccharides- 1 sugar long, building blocks of carbs
Disaccharides- 2 sugars long
Polysaccharides- many repeating monosaccharides
Oligosaccharides- complex carbs, 2-10 monomers long
Monosaccharides
Simplest carb
6 carbon sugars (hexoses) play roles
Glucose=C6H12O6
Fructose is a structural isomer of glucose – molecules with the same formula but bonded
together in different orders
Galactose is a stereoisomer of glucose- molecules with the same molecular formula (same
structural isomer) and same sequence of bonded atoms, only differs in the 3-dimensional
orientations of their atoms in space
These differences account for substantial functional differences between isomers
Your tastebuds can discern them, fructose much sweeter than glucose despite identical
chemical composition.
Enzymes that act on different sugars can distinguish structural isomers and stereoisomers of
the basic 6-carbon skeleton
Glucose
Particularly efficient energy molecule.
During cellular respiration free energy of glucose is converted into stored energy of ATP
Provides raw materials for biosynthesis of amino acids and nucleotides.
Glucose is not the only sugar with the formula C6H12O6
Learning outcomes
1. List the main features of carbs
2. Explain the difference between types of isomer
3. Describe the formation of glycosidic bonds
4. Outline the role of carbs in nature
Carbohydrates
Also called saccharides
Compounds formed from carbon, hydrogen and oxygen
1:2:1 ratio
Formula (CH2O) n, n=number of carbon-hydrate groups
Ready source of energy
C-H covalent bonds hold much energy
Good energy storage molecules
Sugars, starch glucose
Other crabs are structural- cellulose lignin chitin in cell walls
Monosaccharides- 1 sugar long, building blocks of carbs
Disaccharides- 2 sugars long
Polysaccharides- many repeating monosaccharides
Oligosaccharides- complex carbs, 2-10 monomers long
Monosaccharides
Simplest carb
6 carbon sugars (hexoses) play roles
Glucose=C6H12O6
Fructose is a structural isomer of glucose – molecules with the same formula but bonded
together in different orders
Galactose is a stereoisomer of glucose- molecules with the same molecular formula (same
structural isomer) and same sequence of bonded atoms, only differs in the 3-dimensional
orientations of their atoms in space
These differences account for substantial functional differences between isomers
Your tastebuds can discern them, fructose much sweeter than glucose despite identical
chemical composition.
Enzymes that act on different sugars can distinguish structural isomers and stereoisomers of
the basic 6-carbon skeleton
Glucose
Particularly efficient energy molecule.
During cellular respiration free energy of glucose is converted into stored energy of ATP
Provides raw materials for biosynthesis of amino acids and nucleotides.
Glucose is not the only sugar with the formula C6H12O6
