carbohydrates Flashcards
what is a monosaccharide
a sweet ,soluble monomer that cannot be hydrolysed into a simpler sugar
examples of monosaccharides
hexose sugar = glucose , fructose , galactose
pentose sugar = ribose
general formula for a monosaccharide
CnH2n0n
what are the glucose isomers
alpha glucose = H is on top cos its the alpha
CH20H , H , 0H , H ,H
beta glucose = normal , CH2OH , H, OH , H , OH
what is a dissaccharide
two monosaccharides ( sweet and soluble ) linked by a glycosidic bond formed in a condensation reaction ( + water ! )
common disaccharides
alpha glucose + alpha glucose = maltose
glucose + galactose = lacotse
glucose + fructose= sucrose
condensation reaction to form disaccharides
OH from carbon 1 and OH from carbon 4 forms glycosidic linkage ( O ) and an H2O molecule ( 1,4 or 1,6 glycosidic bond )
how do you break disaccharides
adding water in a hydrolysis reaction
why is the structure of glucose useful to its functions
it is small and water soluble so it can be transported easily in the bloodstream
complementary shape to antiport and enzymes so transport and glycolysis can occur
structure of starch
large and insoluble storage molecule made of alpha glucose molecules in two types of chain ( amylose and amylopectin)
amylose vs amylopectin
amylose = 30% - 1,4 glycosidic bond , unbranched, spiralled , more compact for storage
amylopectin = 70 % - 1,4 and 1,6 glycosidic bonds , branched , branches can be broken off easily to fast release energy
glycogen
alpha glucose
animal starch
way of storage in animals
similar to amylopectin structure ( lots of 1-4 and 1-6 glycosidc bonds creating branches )
cellulose
beta glucose
found in plant cell walls
the alternating monomers need to be flipped to create a bond
has a cross link structure
the chains are stacked with hydrogen bonds between the chains
the cross links are between oxygen in the glycosidic bond and carbon 6
