carbohydrates Flashcards
monomers
the smaller units from which larger molecules are made
POLYMERS
are molecules made from a large number of monomers joined together in a chain
organic compounds
contain carbon
why are carbon atoms important
can for 4 covelant bonds making them very stable as they require a large input of energy to break them
carbon atoms cab bond to form straight chains, branched chains, rings.
macromolecules
large molecules
That contain 1000 or more atoms therefore having a high molecular mass
Polymers can be macromolecules, however not all macromolecules are polymers as the subunits of polymers have to be the same repeating units
ratio of h to o in carbs
2:1
monosacchearide examples
triose
pentose
hexose
glucos
galactose
fructose
disaccharide examples
maltose - a glucose and a glucose
sucrose - a glucose and fructose
lactose - a glucose and b galactose
condensation
monomers combione to foem polymers and water is removed - makes glycosydic bonds
hydrolysis
break down polymers with water
reducing sugars
reducing can donate electrons and can be detected in a benedicts test
glucose
fructose
galactose
non reducing sugars
cannot donate electrons
must be hydrolysed into monosaccharides before a benedicts test can occur
sucrose
glucose formula
C6H12O6
difference between a glucose and b glucose
in beta glucose the OH on the right is above the ring’
in a glucose it is below
every glycosydic bond results in one water being removed
so made in condensation
1,4 bonds
bonding long chains
1,6 bonds
bonding branches
maltose types of bond
a 1,4
sucrose types of bond
a 1,2
cellulose types of bond
b 1,4
amylose types of bond
a 1,4
amylopectin types of bond
a 1,4 and a 1,6
example of hydrolytic reactions
in enzymes when breaking food down
disaccharide exaples
maltose
sucrose
lactose
function of starch and glycogen
storage molecules:
compact - large quantities can be stored
insoluble - do not affect the osmotic potential of a cell ensuring cells do not burst or shrink
starch is the storage molecule for
plants
why does starch take a long time to digest
many monomers
helical shape from amylose
starch is made up of these 2 polysacharrides
amylose
amylopectin
amylopectin in starch
contains 1,4 and 1,6 bonds between glucose molecules making it branched
results in terminal glucose molecules trhat can be easily hydrolysed and theredfore a readily available source of energy
glycogen function
storage polysaccaride for animals and fungi
benefit of glycogen is more branched than amylopectin
making it more compact which helps animals to store more
function of high branching in glycogen
more free ends where glucose molecules can either be added or removed allowing for condensation and hydrolysis reactions to occur more rapidly:
storage or release of glucose is more readily available
more compact so can store more
polysaccharides are _____________ in water
insoluble
cellulose structure
polymer consisting of long chains of b glucose joined together by 1, 4 glycosydic bonds
must be rotated 180 degrees to each other
benefit of inverted glucose
many hydrogen bonds form that give cellulose its strength
cellulose function
main component in cell walls due to its strength
high tensile strength means it can withstand turgor pressure
strengthened cell wall provides support to the plant
cellulose fibres are freely permeable which allows water and solutes to leave and reach cell membrane
source of fibre as few organmisms have cellulase
benedicts test for reducing sugars
add benedicts to a sample
heat the test tube
coloured precipitate will form if positive
BLUE TO BRICK RED
make sure benedicts is in excess
