Carbohydrates Flashcards
Types of monosaccharides:3)
alpha glucose and beta glucose structure
what reaction and bond between monosaccharides
glucose, galactose, fructose
condensation, glycosidic
disaccharides:
glucose+ glucose=
glucose+ galactose=
glucose+ fructose=
glucose+ glucose=maltose
glucose+ galactose=lactose
glucose+ fructose= sucrose
starch: what is its structure
why does its structure and properties make it a useful energy store?
test for starch:
mixture of amylose- polysaccharide made of alpha glucose joined by 1-4 glycosidic bonds
amylopectin- polysaccharide made of alpha glucose joined by 1-4 and 1-6 glycosidic bonds
helical- compact, can be stored
branched- large surface area/ many places for amylase to hydrolyse into glucose- faster hydrolysis
insoluble, does not impact water potential of cells
large, does not diffuse out the cell
easily hydrolysed- readily accessible energy source
iodine, yellow to black
cellulose:
structure:
why is useful?
many long, unbranched chains beta glucose joined by 1-4 glycosidic bonds parallel to each other, joined by many hydrogen bonds to form microfibrils- provides high tensile strength to support rigidity and shape of cell walls
impermeable to water
glycogen: structure:
why does its structure and properties make it a useful energy store?
1-4 and 1-6 glycosidic bonds between alpha glucose molecules- highly branched
branched- large surface area/ many places for protein kinase to hydrolyse into glucose- faster hydrolysis
insoluble, does not impact water potential of cells
large, does not diffuse out the cell
easily hydrolysed- readily accessible energy source
Test for reducing and non reducing sugars:
examples of reducing and non reducing sugars:
heat sample with benedicts reagent- blue to brick red- reducing sugar present
heat sample with benedicts reagent- stays blue- negative
add HCl and boil
add NaOH or NaHCO3
repeat benedicts with heat- blue to brick red-positive
sucrose is non reducing
glucose is reducing
