polysaccharides Flashcards
(35 cards)
what are polysaccharides
formed from very large numbers of monosaccharides
what bonds do polysaccharides have
glycosidic
why couldn’t you just store glucose in that form in cells
soluble in waterso would increase concentration of the cell contencts and draw water in by osmosis
how is glucose stored in plant cells
startch
how is glucose stored in animal cells
glycogen
what are the benefits of using startch / glycogen to store glucose
insoluble - no osmatic effect
cannot diffuse out of the cell
compact
carry a lot of enery in c-h and c-c bonds
dice
where can you find startch in high concentrations
seeds + storage organs such as potato tubers
what are the 2 polymers of startch
amylose
amylopectin
amylose structure
linear unbranched
alpha 1- 4 glycosidic bonds
helix
amylopectin structure
a 1-4 glycosidic bonds and a 1-6 glycosidic bonds
branched
how to test for startch
iodine-potassium iodide test
orange brown to blue black
qualitative test
different between glycogen and amylopectin
glycogen more branched
structure of cellulose
long chain of 1-4 glycosidic B glucose units
how does cellulose look like
straight + unbracnhed
B link rotates by 180 degreees
where do hydrogen bonds form in cellulose
between OH groups
makes it structurally stable
how do microfibrili form
paralel cellulose molecules become tightly cross linked by hydrgen bonds
in what are microfibrili held
bundles called fibres
is cellulose permable
freely permable
structure of chitin
beta 1-4 glucose with nitrogen to form a hetropolysaccharide
difference between cellulose and chitin
chitin has amino acid
where can you find chitin
exoskeleton and fungal cell wall
properties of chitin
strong
waterproof
lightweight
similarity of chitin to cellulose
monomers rotated by 180
long parallel chains are cross linked by hydrogen bonds forming microfibrils
cellulose - hydrogen bonds form what
cross-linkages
makes cellulose form long threads called microfibrils
